,,! ,,petrol ,,eng9e ,,books ,,= ,,motor ,,eng9e]s4 ,electrical ,ignition = ,int]nal ,combu/ion ,eng9es4 ,by ,m4 ,a4 ,codd4 #aji illus41 #afc pp41 cr4 #hvo4 #cs4 net4 ,introduction--,pr9ciple ( ,electric ,fl[--,batt]ies--,swit*es--,coils--,auto -,trembl]s--,lodge ,ignition--,di/ributors--,magneto ,ignition--,high ,t5sion ,magnetos--,faults & ,rem$ies--,magneto ,repairs--,induction ,coil ,design--,index4 ,dynamo ,light+ = ,motor ,c>s4 ,by ,m4 ,a4 ,codd1 ,au?or ( 8,electrical ,ignition = ,int]nal ,combu/ion ,eng9es40 #abh illus41 vi #if pp4 #hvo4 #bs4 #f;d4 net4 ,introduction & ,g5]al ,pr9ciples--,fitt+ ! ,sy/em--,wir+ ! ,c>--,p]man5t ,magnet ,sy/em--,p]man5t & ,electro-,magnet ,sy/em--,electro-,magnetically ,gov]n$ ,sy/em--,electro-,magnetically ,controll$ ,sy/em--,me*anically ,controll$ ,sy/em--,hot ,wire ,controll$ ,sy/em--,"s useful ,accessories--,upkeep1 ,ma9t5ance1 & ,location ( ,faults--,index4 ,engli%-,fr5* & ,fr5*-,engli% ,diction>y ( ! ,motor ,c>1 ,cycle & ,boat4 ,by ,fr$]ick ,lucas4 #aga pp41 cr4 #hvo4 #bs4 net4 ,motor ,cycles1 ,side ,c>s & ,cycle ,c>s1 ,con/ruction1 ,managem5t & ,repair4 ,by ,v4 ,w4 ,page1 ,m4,e4 ,a compreh5sive non-te*nical treatise1 def9+ all =ms ( ! light] self-propell$ vehicles1 pr9ciples ( op]ation1 con/ruction1 & practical application ( compon5t p>ts4 #hvo1 #cdd illus41 #eej pp4 7,new ,york47 #fs4 #f;d4 net4 ,! ,mod]n ,gasol5e ,automobile1 its ,design1 ,con/ruction1 ,ma9t5ance & ,repair4 ,by ,victor ,w4 ,page1 ,m4,e41 late ,te*nical ,editor ( ! 8,automobile ,j\rnal40 #ejj illus41 #fic pp41 #hvo4 7,new ,york47 #abs4 net4 ,draw+s = ,m$ium ,siz$ ,repetition ,"w1 ) ,examples ( ,draw+s = ,motor-,c> ,p>ts4 ,by ,r4 ,d4 ,sp9ney1 ,a4,m4,i4,me*4,e4 #dg illus41 #acj pp41 #hvo4 #cs4 #f;d4 net4 ,motor ,body ,build+ 9 all its bran*es4 ,by ,c4 ,w4 ,t]ry1 ,organiz] & ,inspector ( ! ,city & ,guilds ( ,london ,in/itute4 ,) additional matt] by ,ar?ur ,hall1 ,graduate memb] ( 8,! ,in/itute ( ,briti% ,c>riage ,manufactur]s10 #a/ class c]tificate 9 hon\rs ( ! ,city & ,guilds ( ,london ,in/itute1 & o!r aw>ds2 ,in/ructor 9 ,motor ,body ,build+1 ,municipal ,te*nical ,college1 ,brighton1 etc41 etc4 ,m$ium #hvo1 #bef pp41 #ae illus41 #e plates4 #ajs4 #f;d4 net4 ,e4 ,f4 ,n4 ,,spon1 ,,ltd41 #eg ,,haym>ket1 ,,london1 ,s4,w4 ,! ,petrol ,eng9e ,a ,text-book deal+ ) ! ,pr9ciples ( ,design & ,con/ruction1 ) a ,special ,*apt] on ! ,two-/roke ,eng9e ,by ,,francis ,,john ,,kean ,b4,,sc4 7,,lond472 ,m4,i4,m4,e4 ,fir/-,class ,hon\rman 9 ,eng9e]+2 ,head ( ! ,motor ,c> ,eng9e]+ ,dep>tm5t ( ! ,polyte*nic ,s*ool ( ,eng9e]+1 ,reg5t ,/reet1 ,london1 ,w42 ,=m]ly ,lectur] on ,exp]im5tal ,eng9e]+ at ,mc,gill ,univ]sity1 ,montreal1 ,canada #ga ,,illu/rations ,colophon ,london ,e4 ,f4 ,n4 ,,spon1 ,,limit$1 #eg ,,haym>ket ,new ,york ,,spon ,,*amb]la91 #abc ,,lib]ty ,,/reet #aiae ,,cont5ts ,,page ,,li/ ,,( ,,illu/rations ix ,,preface xiii ,,*apt] ,i ,,g5]al ,,pr9ciples-- ,explosive ,mixtures #a ,! ,mean+ ( ,suction #b ,! ,mean+ ( ,compression #c ,! ,mean+ ( a ,/roke #c ,! ,otto ,cycle #e ,,*apt] ,,ii ,,description ,,( ,a ,,typical ,,petrol ,,eng9e-- ,! ,cyl9d] #h ,,*apt] ,,iii ,,eng9e ,,details-- ,! ,pi/on #ag ,! ,connect+ ,rod #ba ,! ,crank%aft #bc ,! ,fly:eel #be ,,*apt] ,,iv ,,! ,,valves-- ,poppet ,valves #bi ,sleeve ,valves #ca ,! ,cam%afts & ,ecc5tric ,%afts #cc ,! ,tim+ ,:eels #cg ,! ,crank*amb] #ch ,,*apt] ,v ,,! ,,c>burettor ,,& ,,c>buration-- ,! ,float ,*amb] #dd ,! ,petrol ,jet & ,*oke ,tube #df ,! ,mix+ ,*amb] & ,?rottle ,valve #dg ,rec5t ,improvem5ts 9 ,c>burettors #dg ,pressure ,fe$ & ,gravity ,fe$ #ej ,,*apt] ,,vi ,,ignition ,,& ,,ignition ,,devices-- ,! ,sp>k+ ,plug #ea ,! ,high ,t5sion ,magneto #eb ,! ,ignition ,coil #eg ,wir+ ,diagram = ,magneto ,ignition ,sy/em #fj ,wir+ ,diagram = a ,coil ,ignition ,sy/em #fj ,tim+ ! ,ignition #fb ,,*apt] ,,vii ,,lubrication-- ,prop]ties ( ,oils #fc ,spla% ,sy/em ( ,lubrication #fc ,improv$ ,sy/em ( ,spla% ,lubrication #fd ,=c$ ,lubrication #fe ,,*apt] ,,viii ,,cool+-- ,natural or ,!rmo-,syphon ,circulation #fi ,=c$ or ,pump ,circulation #ga ,,*apt] ,,ix ,,! ,,po9ts ,,( ,a ,,good ,,eng9e-- ,*oos+ ! ,numb] ( ,cyl9d]s #ge ,! ,"q ( ! ,valves #gg ,economy & ,durability #gi ,,*apt] ,x ,,two-,,/roke ,,eng9es-- ,! ,two-port ,two-/roke ,eng9e #hj ,! 8,kean0 ,duplex ,air ,scav5g+ ,eng9e #he ,! ,tw9-cyl9d] ,two-/roke ,eng9e #if ,,*apt] ,,xi ,,horse-,,p[] ,,& ,,! ,,indicator ,,diagram-- ,"w #ih ,p[] #ih ,brake ,horse-p[] #ii ,rat$ ,horse-p[] #ajj ,indicat$ ,horse-p[] #aja ,! ,indicator ,diagram #ajb ,,*apt] ,,xii ,,liquid ,,fuels-- ,petrol #ajh ,b5zol #ajh ,alcohol #aji ,p>aff9 #aji ,!rmal ,effici5cy #aaj ,,app5dix ,,eng9e ,,tr\bles #aac ,,tim+ ,,! ,,ignition #aae ,,index #aag ,,li/ ,,( ,,illu/rations ,,fig4 ,,description4 ,,page #a4 ,diagram to expla9 ! mean+ ( ,suction #a #b4 ,diagram to expla9 ! mean+ ( ,compression #b #c4 ,otto ,cycle4 ,! ,suction ,/roke #c #d4 ,otto ,cycle4 ,! ,compression ,/roke #d #e4 ,otto ,cycle4 ,! ,p[] ,/roke #e #f4 ,otto ,cycle4 ,! ,exhau/ ,/roke #f #g4 ,g5]al arrangem5t ( a ,mod]n ,petrol ,eng9e #i #h4 ,sectional ,draw+ ( a ,t-head$ ,cyl9d] #ab #i4 ,outside ,view ( a ,wat]-jacket$ ,cyl9d] #ac #aj4 ,/ud #ad #aa4 ,bolt #ad #ab4 ,setscrew #ad #ac4 ,motor-cycle ,eng9e ) air-cool$ ,cyl9d] #ad #ad4 ,a]oplane ,eng9e ,cyl9d] #ae #ae4 ,ca/-iron ,pi/on #ah #af4 ,me?od ( fix+ ,gudgeon ,p9 #ai #ag4 ,?ree =ms ( ,pi/on-head #ai #ah4 ,connect+ ,rod 9 ! =m ( a ,/amp+ #bj #ai4 ,connect+ ,rod turn$ f a solid ,b> ( ,/eel #ba #bj4 ,crankp9 & ,crankwebs #bb #ba4 ,f\r-?r[ ,crank%aft #bc #bb4 ,motor-cycle ,crankp9 #bd #bc4 ,balanc$ ,crank #be #bd4 ,sket* %[+ ! unbalanc$ portion ( a ,crank #be #be4 ,balanc$ ,two-?r[ ,crank%aft #bf #bf4 ,=ce act+ on a ,fly:eel ,rim #bf #bg4 ,built-up ,/eel ,fly:eel #bg #bh4 ,fly:eel turn$ f a ,/eel ,/amp+ #bh #bi4 ,g5]al arrangem5t ( a ,poppet ,valve #cj #cj4 ,sectional ,draw+ ( ! ,cyl9d] ( a ,sleeve-valve ,eng9e #ca #ca4 ,sectional ,draw+ ( ! ,cyl9d] ( a ,sleeve-valve ,eng9e #cb #cb4 ,poppet ,valve-head1 %[+ ,slot = ,gr9d+-9 purposes #cd #cc4 ,inlet & ,exhau/ ,valve ,cams #cd #cd4 ,ecc5tric ,%eave & ,rod = a ,sleeve ,valve #cf #ce4 ,a ,pair ( ,tim+ ,:eels #cg #cf4 ,a ,crank ,*amb]1 outside end view #ci #cg4 ,a ,crank ,*amb]1 sectional view #ci #ch4 ,g5]al arrangem5t ( ! ,c>burett+ ,plant #dc #ci4 ,sectional ,draw+ ( a ,c>burettor ( ! ,jet ,type #dd #dj4 ,pla9 ,=m ( ! ,*oke ,tube #dg #da4 ,petrol ,jet = atomis+ ! ,petrol #dh #db4 ,comp5sat$ ,petrol ,jet #dh #dc4 ,automatic ,spr+-controll$ ,extra-air ,valve #di #dd4 ,plan ,view ( ,automatic ,extra-air ,valve #di #de4 ,sectional ,draw+ ( a ,sp>k+ ,plug #ea #df4 ,a ,sp>k+ ,plug #eb #dg4 ,outside ,view ( a ,high-t5sion ,magneto #eb #dh4 ,view ( ,high ,t5sion ,magneto %[+ ,di/ributor & ,contact ,break] #ec #di4 ,end ,view ( ,high ,t5sion ,magneto #ed #ej4 ,an ,ignition ,coil #ef #ea4 ,an ,ignition ,coil ,case #eg #eb4 ,l[ ,t5sion ,contact ,break] = ,coil ,ignition 7,wipe ,=m7 #eh #ec4 ,wir+ ,diagram = ,f\r ,cyl9d] ,eng9e ) ,magneto ,ignition 7,high ,t5sion7 #fj #ed4 ,wir+ ,diagram = ,f\r ,cyl9d] ,eng9e ) ,trembl] ,coil ,ignition #fa #ee4 ,improv$ ,sy/em ( ,spla% ,lubrication #fd #ef4 ,sectional ,view ( ,connect+ ,rod end1 %[+ ,scoop & ,oil ,tr\gh #fe #eg4 ,=c$ ,lubrication ,sy/em #ff #eh4 ,sectional ,view ( ,rot>y ,oil ,pump #fg #ei4 ,a ,rot>y ,oil ,pump #fg #fj4 ,!rmo-syphon ,wat] ,cool+ ,sy/em #fi #fa4 ,=c$ ,wat] ,circulation by means ( a ,pump #gj #fb4 ,=ms ( ,wat] ,pip+ #gd #fc4 ,two-port ,two-/roke ,eng9e ) ,crank*amb] ,compression #ha #fd4 ,diagrammatic ,sket* ( a ,duplex ,two-/roke ,air ,scav5g+ ,eng9e #hg #fe4 ,g5]al ,arrangem5t ( ! 8,kean0 ,two-/roke ,eng9e #ia #ff4 ,tw9-cyl9d] ,two-/roke ,eng9e ) ,crank*amb] ,compression #ig #fg4 ,petrol ,eng9e ,brake #ajj #fh4 ,=ce-space or 8,"w0 ,diagram #ajc #fi4 ,petrol ,eng9e ,indicator ,diagram ,f\r-/roke ,cycle #aje #gj4 ,petrol ,indicator ,diagram = a ,two-/roke ,eng9e #ajf #ga4 ,diagram ( ,valve-sett+ #aaf ,,preface ,?is book deals ) pr9ciples4 ,!re are _m books :i* give a descriptive acc\nt ( exi/+ types ( eng9es1 b my object 9 writ+ ?is volume has be5 to assi/ ! read] to obta9 ?or\ghly s\nd notions ( ! pr9ciples ( design & con/ruction :i* und]lie all curr5t practice4 ,if a man und]/&s1 = example1 ! con/ruction ( ! elem5ts ( a c>burettor & h[ !y ought to p]=m _! sev]al functions1 he %\ld h no difficulty 9 und]/&+ any special type ( c>burettor plac$ ^u ! m>ket4 ,9 deal+ ) ! subject ( ignition ,i h purposely avoid$ any detail$ explanation ( ! mann] 9 :i* ! sp>k dis*>ge is produc$1 because ,i felt t x introduces new ideas & probably causes ! read] to lose sight ( ! fact t ! magneto is only1 aft] all1 an accessory1 al?\gh ( c\rse a mo/ important "o4 ,i hope t ! acc\nts ( my exp]im5ts ) ! two-/roke w be ( "s s]vice to inv5tors & o!rs2 ! _m extraord9>y breakd[ns1 defects & adv5tures enc\nt]$ dur+ ?is p]iod ( my c>e] h n be5 ins]t$ because !y w\ld und\bt$ly cause ! read] to =get1 = ! "t be+1 8 fundam5tal pr9ciples4 ,my colleague1 ,mr4 ,oliv] ,mit*ell1 :o lectures at ! ,polyte*nic on 8,motor ,c> ,managem5t & ,inspection10 has read ?r\gh ! pro(s = me & v k9dly sugge/$ sev]al small additions to ! text1 :i* ,i h incorporat$2 he also sugge/$ ! ins]tion ( ! valve-sett+ diagram 9 ! ,app5dix4 ,my ?anks are due to ,mr4 ,mit*ell = 8 s]vices & also to my wife = h] assi/ance 9 ! prep>ation ( ! ,index4 ,,francis ,,john ,,kean4 ,,! ,,polyte*nic ,,s*ool ,,( ,,eng9e]+1 ,,reg5t ,,/reet1 ,,london1 ,w4 ,july1 #aiae4 ,,! ,,petrol ,,eng9e ,,*apt] ,i ,,g5]al ,,pr9ciples ,illu/ration3 ,,fig4 #a4--;,,diagram ,,to ,,expla9 ,,! ,,mean+ ,,( 8,,suction40 ,explosive ,mixtures4--,if a small quantity ( liquid petrol or b5zol be plac$ 9 an op5 vessel & expos$ to a curr5t ( air x w quickly disappe> or evaporate4 ,we say t ! liquid petrol has be5 vaporiz$ or turn$ into petrol vap\r4 ,a mixture ( air & petrol vap\r c be ignit$ & burnt1 ! rate ( burn+ be+ affect$ by ! /r5g? ( ! mixture4 ,! /r5g? ( ! mixture is det]m9$ by measur+ ! respective volumes ( air & petrol vap\r pres5t 9 a kn[n volume ( ! mixture4 ,x is possible to =m a mixture ( air & petrol vap\r 9 su* proportions t :5 ignit$ by an electric sp>k x w be completely burnt at su* a rate t ! combu/ion is almo/ in/antane\s1 i4e41 x w explode4 ,?is mixture ( air & petrol vap\r w\ld !n be ref]r$ to z an explosive mixture & w\ld be suitable = supply+ to ! cyl9d] ( a petrol eng9e4 ,illu/ration3 ,,fig4 #b4--;,,diagram ,,to ,,expla9 ,,! ,,mean+ ,,( 8,,compression40 ,! ,mean+ ( ,suction4--,imag9e an iron cyl9d] ,a 7,fig4 #a7 held d[n on a rigid base ,c & fitt$ ) a gas-tight pi/on ,b4 ,if we pull ! pi/on d[n %>ply to ! position %[n 9 ,fig4 #b we w realize t !re is app>5tly "s =ce inside ! cyl9d] :i* is try+ to suck ! pi/on up aga94 ,! fact t ! pi/on is be+ )drawn & no m air or gas admitt$ above x to fill up ! volume x has displac$ on its desc5t causes a p>tial vacuum 9 ! cyl9d]4 ,n[ if by means ( a tap or valve ( "s k9d we c\ld put ! cyl9d] 9 communication ) ! atmosph]e1 air w\ld ru% 9 & fill up ! cyl9d] until ! pressure ( ! gases 9 x became equal to atmosph]ic pressure1 :5 no m air c\ld ent]1 because !re w\ld be no excess ( pressure to =ce x 94 ,9 te*nical language we w\ld say1 8! pi/on has suck$ 9 a *>ge ( air0 ?r\gh ! tap or valve4 ,illu/ration3 ,,fig4 #c4--,,otto ,,cycle4 ,,! ,,suction ,,/roke4 ,! ,mean+ ( ,compression4--,close ! tap or valve & pu% ! pi/on up aga9 %>ply to its orig9al position ( ,fig4 #a4 ,y w n[ enc\nt] consid]able resi/ance & exp]i5ce a =ce pu%+ d[n aga9/ y because y are r$uc+ ! volume ( ! gas & !reby increas+ its pressure2 t is to say1 y are compress+ ! gas1 because y are n[ mak+ an am\nt ( gas t rec5tly occupi$ ! :ole cyl9d] fit itself into ! small space betwe5 ! top ( ! cyl9d] & ! cr[n ( ! pi/on4 ,9 te*nical language y w\ld say1 8! pi/on has n[ compress$ ! *>ge0 ( gas )9 ! cyl9d]4 ,illu/ration3 ,,fig4 #d4--,,otto ,,cycle4 ,,! ,,compression ,,/roke4 ,! ,mean+1 ( a ,/roke4--,9 an eng9e su* z is %[n diagrammatically 9 ,figs4 #c & #d1 :5 ! pi/on ,p moves f its topmo/ position 9 ! cyl9d] d[n to its v l[e/ position we say x has complet$ a d[n/roke1 & :5 x moves upw>ds f its l[e/ to its highe/ position we say ! pi/on has complet$ an up/roke4 ,! l5g? ( ! pi/on's /roke is equal to twice ! l5g? ( ! crank radius ,r1 & is measur$ by obs]v+ ! di/ance mov$ by ! pi/on 9 travell+ f its highe/ position 9 ! cyl9d] to its l[e/ or vice v]sa4 ,! space exi/+ above ! pi/on betwe5 x & ! cyl9d] head :5 ! pi/on has rea*$ its highe/ position 9 ! cyl9d] is call$ ! cle>ance space4 ,x is also ref]r$ to z ! combu/ion *amb]1 or *amb] 9 :i* ! petrol gas is explod$4 ,:5 ! pi/on is ei!r at ! top or bottom ( its /roke ! crank radius ,r & connect+ rod ,t are 9 "o & ! same /raight l9e2 "u ^! conditions we say ! crank is on its inn] or out] dead-c5tre4 ,! ,otto ,cycle4--,mo/ petrol eng9es op]ate on :at is kn[n z ! 8,otto0 cycle1 9 :i* ! cycle ( ev5ts is complet$ once 9 e f\r /rokes 7or two revolutions7 made by ! eng9e4 ,! 8,otto0 cycle is !re=e usually ref]r$ to z ! f\r-/roke cycle4 ,9 ! accompany+ diagrams 7,figs4 #c1 #d1 #e1 & #f7 we %[ 9 diagrammatic =m ! int]ior ( a petrol eng9e cyl9d] fitt$ ) mu%room type valves4 ,illu/ration3 ,,fig4 #e4--,,otto ,,cycle4 ,,! ,,p[] ,,/roke4 ,9 /udy+ ! figures we assume ! eng9e is be+ crank$ r\nd by h& 9 ! direction ( ! arr[ :ile we view x f ! 8fly:eel0 end 7i4e4 ! end adjac5t to ! driv]'s seat71 !n ,a is ! pipe :i* leads ! mixture ( air & petrol vap\r f ! c>burettor to ! cyl9d] & is call$ ! induction pipe4 ,c is ! cyl9d]1 ,p ! pi/on1 ,i ! inlet valve1 ,e ! exhau/ valve1 ,t ! connect+ rod1 ,r ! crank1 & ,s ! sp>k+ plug4 ,! pipe ,b :i* leads ! burnt gases f ! exhau/ valve to ! sil5c] is call$ ! exhau/ pipe4 ,! cycle ( op]ations is z foll[s3-- ,illu/ration3 ,,fig4 #f4--,,otto ,,cycle4 ,,! ,,exhau/ ,,/roke4 7#a7 ,on ! fir/ d[n/roke made by ! pi/on a suction effect or p>tial vacuum is produc$ 9 ! cyl9d]2 ! air & petrol vap\r 9 ! induction pipe be+ at atmosph]ic pressure1 :i* is 9 excess ( t n[ exi/+ 9 ! cyl9d]1 fl[ into ! cyl9d] z soon z ! inlet valve ,i is op5$ by ! eng9e me*anism4 ,at ! end ( ?is1 ! suction /roke1 ! inlet valve closes & traps ! *>ge ( explosive mixture 9 ! eng9e cyl9d]4 ,?is is %[n 9 ,fig4 #c4 7#b7 ,on ! fir/ up/roke made by ! pi/on ! *>ge ( explosive mixture is compress$ ready = fir+4 ,bo? valves are %ut4 ,?is is %[n 9 ,fig4 #d4 7#c7 ,on ! second d[n/roke made by ! pi/on ! sp>k+ plug ,s passes a sp>k :i* explodes ! *>ge at ! v comm5cem5t ( ! d[nw>d movem5t ( ! pi/on4 ,! =ce ( ! explosion drives ! pi/on d[nw>ds1 do+ useful "w4 ,bo? valves are %ut4 ,?is is ! p[] /roke1 & suffici5t p[] mu/ be develop$ on ?is /roke n only to d ! "w requir$ f ! eng9e b also to tide x ov] ! o!r ?ree idle /rokes4 ,on ?is /roke ! pi/on drives ! crank by means ( ! connect+ rod1 b on ! o!r ?ree /rokes ( ! cycle ! crank has to drive ! pi/on by means ( ! p[] or en]gy /or$ 9 ! eng9e fly:eel on ! p[] /roke4 ,t[>ds ! end ( ! p[] /roke 7or explosion /roke7 ! eng9e me*anism op5s ! exhau/ valve ,e & all[s "p ( ! burnt gases to escape to ! sil5c] along ! exhau/ pipe4 ,?is is %[n 9 ,fig4 #e4 7#d7 ,on ! second up/roke ( ! cycle ! pi/on pu%es ! rema9+ burnt gases out ( ! cyl9d] ?r\gh ! exhau/ valve4 ,:5 ! pi/on rea*es ! top ( its /roke ! exhau/ valve closes4 ,?is is %[n 9 ,fig4 #f4 ,! cycle ( op]ations !n beg9s aga91 giv+ "o p[] /roke & ?ree idle /rokes ea* "t z already describ$4 ,,*apt] ,,ii ,,description ,,( ,a ,,typical ,,petrol ,,eng9e ,= ! purpose ( expla9+ ! cycle ( op]ations we h consid]$ only a diagrammatic sket* ( an imag9>y motor-c> eng9e1 b 9 ,fig4 #g we illu/rate an up-to-date motor-c> eng9e4 ,9 ! fir/ place we note ! position & arrangem5t ( ! f\r wat]-cool$ cyl9d]s1 ,a#a1 ,a#b1 ,a#c1 ,a#d1 conta9+ _! pi/ons & mu%room type valves4 ,^! are conv5i5tly plac$ 9 a v]tical position & m\nt$ on top ( ! crank*amb] ,c1 to ! bottom ( :i* is atta*$ ! oil-base ,b4 ,at ! front ( ! eng9e are %[n ! tim+ :eels 9 _! cas+ ,e1 & at ! re> end ! fly:eel ,f4 ,! />t+-h&le connexion is at ,s1 ! fan pulley be+ %[n at ,m4 ,! high t5sion magneto :i* supplies ! curr5t to ! sp>k+ plugs is %[n at ,h1 & ,i is ! induction pipe connect$ to ! c>burettor ,k4 ,! wat] circulat+ pump is on ! (f side ( ! eng9e & does n appe> 9 ! illu/ration1 b ,l#a is ! inlet wat] pipe lead+ f ! radiator 7n %[n7 to ! wat] pump1 & ,l#b is ! deliv]y pipe f ! pump to ! respective cyl9d] jackets1 ,l#c be+ ! outlet wat] pipe4 ,! exhau/ pipe is %[n at ,d1 & ! oil pump at ,p4 ,! valve spr+s1 valve tappets & guides c also be cle>ly se54 ,9 exam9+ ! sev]al p>ts ( ! eng9e 9 detail we mu/ n lose sight ( _! respective positions 9 ! g5]al arrangem5t view ( ,fig4 #g4 ,illu/ration3 ,,fig4 #g4--;,,g5]al ,,arrangem5t ,,( ,a ,,mod]n ,,petrol ,,eng9e4 ,! ,cyl9d]4--,probably "o ( ! mo/ important p>ts ( an eng9e is ! cyl9d]4 ,z we h already se51 x is inside ! cyl9d] t ! *>ge ( petrol vap\r & air is explod$ & completely burnt4 ,! heat en]gy ( ! petrol mixture :i* is lib]at$ by ! explosion is imm$iately trans=m$ into me*anical "w & propels ! pi/on =w>d l a projectile f a gun4 ,b we mu/ also notice t our pres5t-day arrangem5ts 7clev] z !y are7 are by no means p]fect1 & we _c1 ev5 "u ! mo/ fav\rable circum/ances1 conv]t m ?an ab\t "o-?ird ( ! heat en]gy ( ! petrol mixture into ! me*anical en]gy ( ! mov+ pi/on4 ,( ! rema9+ two-?irds ( ! heat1 "p is us$ up 9 heat+ ! cyl9d] walls1 ! pi/on & ! valves1 & ! rema9d] goes out ) ! exhau/ gases to ! sil5c]1 f9ally escap+ to ! outside air4 ,?us two important facts are br\ght to our notice3-- 7#a7 ,! reason :y we use petrol to drive our motor-c>s is because petrol 7& c]ta9 o!r liquid fuels su* z b5zol1 etc47 conta9s )9 itself a /ore ( en]gy :i* c be lib]at$ z heat :5 ! fuel is burnt or explod$ 9 ! pres5ce ( air 9 ! eng9e cyl9d]4 7#b7 ,at ! pres5t day1 ev5 ) our mo/ up-to-date contrivances1 we _c make use ( two-?irds ( ! available heat 9 our petrol4 ,in/ead ( be+ able to turn ?is heat into useful me*anical "w1 we are compell$ to ?r[ x away--to wa/e x4 ,fur!r ?an t1 we h to make special provision to ensure t x %all be wa/$ z quickly z possible & z easily z possible4 ,we take out ! greate/ am\nt t we c possibly turn into "w & !n ha/5 to dissipate ! rema9+ two-?irds4 ,we ca/ holl[ *amb]s on ! outside ( our cyl9d]s ?r\gh :i* we circulate cold wat] to keep d[n ! heat 9 ! cyl9d] walls2 if our cyl9d] walls & pi/on get too hot our eng9e may seize up1 !re=e we mu/ cool !m to ensure satisfactory runn+4 ,aga9 we make l>ge exhau/ valves & provide a free escape ?r\gh ! sil5c] = ! exhau/ gases1 s t :5 we h snat*$ our useful "o-?ird ( ! heat supply we may ?r[ ! rema9d] away into ! atmosph]e z rapidly z possible4--?is "p is ( no use to u1 we _c turn x into "w1 !n :y let x /ay "h & heat our cyl9d] walls & pi/on /ill fur!r8 ,x is a good plan to ext5d ?is holl[ *amb]1 conta9+ ! wat] 9 circulation1 at lea/ r\nd ! :ole ( ! combu/ion *amb] & all r\nd ! inlet & exhau/ valve passages & d[n ! b>rel ( ! cyl9d] z f> z ! walls are likely to come into contact ) ! hot gases f ! explosions4 ,we ref] to ?is holl[ *amb]1 ) its circulat+ wat]1 z ! wat]-jacket ( ! cyl9d]4 ,x is n absolutely ess5tial to h our cyl9d] wat]-jacket$1 especially ) small eng9es = motor-cycles & eng9es = a]oplanes :i* h revolv+ cyl9d]s1 b x is practically ess5tial 9 ne>ly all o!r cases4 ,ev5 9 ! special cases m5tion$ x is f\nd necess>y to =m special heat radiat+ f9s on ! outside ( ! heat$ walls to assi/ 9 dissipat+ or gett+ rid ( ! surplus heat & prev5t+ seizure ( ! pi/on )9 ! cyl9d]4 ,^! f9s are cle>ly se5 on ! cyl9d] ( ! motor-cycle eng9e %[n 9 ,fig4 #ac4 ,?us we may say t motor-c> eng9e cyl9d]s are b\nd to be wat]-jacket$1 i4e41 to h a holl[ space r\nd !m conta9+ wat] 9 circulation4 ,! cyl9d]s !mselves are ne>ly always made 9 ! =m ( iron ca/+s & ! jacket spaces =m "p ( ! cyl9d] ca/+ z a g5]al rule1 b occasionally ! wat]-jacket space is =m$ by atta*+ plates or tubes to ! cyl9d] ca/+ by means ( bolts or screws--n an easy ?+ to arrange successfully1 z x requires wat]-tight jo9ts4 ,! proc$ure = manufactur+ a motor-c> cyl9d] is fir/ ( all to design & calculate ! proportions ( ! v>i\s p>ts & get out a set ( work+ draw+s4 ,f ^! draw+s we get patt]ns & core-boxes made 9 wood4 ,! patt]ns are ! exact %ape ( ! f9i%$ cyl9d] on ! outside1 & ! core-boxes are ! exact %ape ( ! inside ( ! f9i%$ cyl9d] 7except 9 s f> z all[ance has to be made = p>ts :i* mu/ aft]w>ds be ma*9$74 ,! patt]ns are pu%$ d[n into ! m\ld+ s& 9 ! f\ndry1 & :5 )drawn leave _! impression1 ?us =m+ m\lds4 ,! core-boxes are fill$ ) s&1 :i* :5 )drawn furni%es u ) masses ( s& t are ! c\nt]p>t ( ! int]ior ( ! cyl9d] 9 %ape4 ,^! cores are support$ c5trally 9 ! m\ld 7:i* is usually 9 halves1 or m ?an two p>ts71 :ile ! molt5 iron is p\r$ into ! int]v5+ space to =m ! iron ca/+4 ,:5 ! ca/+ has cool$ d[n ! s& c be clean$ (f q easily4 ,"o set ( patt]ns & core-boxes w ?us produce q a numb] ( cyl9d] ca/+s1 ea* be+ simil> 9 e respect to ! o!r1 ! process be+ a quick & fairly *eap me?od ( reproduction4 ,lat] on ! cyl9d] b>rel has to be ma*9$ & bor$ out true to v f9e limits by ! use ( bor+ tools & "s k9d ( bor+ ma*9e or la!4 ,! flanges or flat faces h to be plan$ true 9 a plan+ ma*9e & ! valve /em guides & valve seat+s mu/ be c>efully & truly ma*9$ to correct size & %ape4 ,illu/ration3 ,,fig4 #h4--,,sectional ,,draw+ ,,( ,a ,t-,,head$ ,,wat]-,,jacket$ ,,cyl9d]4 ,,valves ,,on ,,opposite ,,sides ,,( ,,cyl9d]4 ,illu/ration3 ,,fig4 #i4--,,outside ,,view ,,( ,a ,,wat]-,,jacket$ ,,cyl9d]4 ,figs4 #h & #i %[ two views ( a s+le motor-c> eng9e cyl9d]1 ! wat]-jacket =m+ "p ( ! cyl9d] ca/+4 ,9 ! figures ,c is ! cyl9d] b>rel or bore2 ,j ! wat]-jacket2 ,i ! inlet = ! jacket wat]2 ,o ! outlet = ! jacket wat]2 ,d is = ! compression tap2 ,s = ! sp>k+ plug2 ,v#a1 ,v#b are ! valve seats2 ,g#a1 ,g#b are ! valve /em guides2 ,h#a1 ,h#b are caps :i* may be remov$ :5 ! valves are be+ put 9 or tak5 out2 f#a1 f#b1 f#c1 f#d1 f#e are call$ flanges4 ,! flange f#a is us$ = atta*+ ! cyl9d] to ! crank*amb]2 :ile x is q true t ! =ce ( ! explosion )9 ! cyl9d] drives ! pi/on d[nw>ds1 x is equally true t x also t5ds to =ce ! cyl9d] head (f or to bl[ ! cyl9d] ca/+ upw>ds (f ! crank*amb]1 unless x is securely fa/5$ to x by means ( screws or bolts pass+ ?r\gh ! flange f#a4 ,! flanges1 f#b1 f#c are = ! inlet & outlet wat] pipe atta*m5ts1 & f#d1 f#e are = ! induction pipe & exhau/ pipe connexions4 ,g5]ally ! pipes w h flanges & be held tight aga9/ ! flanges on ! cyl9d] ca/+ by means ( screws or /uds4 ,figs4 #aj1 #aa1 & #ab %[ h[ two metal flanges are held 9 contact by means ( screws or /uds or bolts1 & !y also %[ ! pack+ mat]ials betwe5 ! metal surfaces :i* keep ! jo9t tight & prev5t wat] or gas leak+ across ! flanges & escap+ to ! outside air1 or air leak+ 9 if ! int]nal pressure is bel[ t ( ! atmosph]e4 ,illu/ration3 ,,/ud ,,fig4 #aj4 ,illu/ration3 ,,bolt ,,fig4 #aa4 ,illu/ration3 ,,setscrew ,,fig4 #ab4 ,illu/ration3 ,,fig4 #ac4--,,motor-,,cycle ,,eng9e ,,) ,,an ,l-,,head$ ,,air-,,cool$ ,,cyl9d]4 ,,valves ,,bo? ,,on ,,same ,,side ,,( ,,cyl9d]4 ,illu/ration3 ,,fig4 #ad4--,,sectional ,,draw+ ,,( ,a ,,built-,,up ,,cyl9d] ,,suitable ,,= ,,an ,,a]oplane ,,eng9e4 ,9 ,figs4 #h & #i ! valves are plac$ "o on ea* side ( ! cyl9d]1 ?is =m ( cyl9d] be+ kn[n z a ,t-head$ cyl9d]1 b x is r m usual "h 9 ,engl& to place bo? valves on ! same side ( ! cyl9d] & next to ea* o!r z indicat$ 9 ,fig4 #ac1 ?is =m ( cyl9d] be+ kn[n z an ,l-head$ cyl9d]4 ,! *ief object is ( c\rse to avoid ! use ( two valve %afts & also to produce a neat] look+ eng9e1 b ! ,t-head$ design is bett] clean$ or scav5g$ by ! passage ( ! inlet & exhau/ gases4 ,:5 a motor-c> eng9e has two cyl9d]s we frequ5tly f9d !m bo? 9 a s+le ca/+1 hav+ a common wat]-jacket1 & !n we say !y are ca/ 9 pairs4 ,a f\r-cyl9d] eng9e may ?us h3 7#a7 ,cyl9d]s ca/ sep>ately2 7#b7 ,cyl9d]s ca/ 9 pairs2 7#c7 ,cyl9d]s ca/ en bloc2 or all f\r 9 a s+le l>ge ca/+4 ,! ?ird me?od is *eape/ 9 fir/ co/1 b 9 ! ev5t ( breakage w become ! mo/ exp5sive4 ,! second me?od is a s\nd compromise4 ,an example ( a built-up cyl9d] & wat]-jacket is %[n 9 ,fig4 #ad1 ! cyl9d] b>rel be+ ( /eel tube ) /eel flanges1 & ! wat]-jacket be+ =m$ by copp] tube slipp$ ov] ! outside ( ! /eel cyl9d]4 ,its great advantage lies 9 ! r$uction ( weight1 & x is ?us l>gely us$ = a]oplane "w4 ,! valves w\ld !n be fitt$ 9 ! top cov] ( ! cyl9d] & driv5 by ov]head ge>+4 ,,*apt] ,,iii ,,eng9e ,,details ,! ,pi/on is p]haps ! mo/ important detail to consid]1 = x is on ! pi/on t ! =ce ( ! explosion acts :5 ! heat en]gy is conv]t$ into me*anical en]gy4 ,x mu/ be made suffici5tly /rong to )/& ! bur/+ effect ( successive explosions1 & yet if we make ! metal too ?ick x w reta9 too mu* ( ! wa/e heat & ! pi/on may seize 9 ! cyl9d] due to expansion4 ,to und]/& :y ! pi/on is likely to seize 9 ! cyl9d] we h only to rememb] t :5 a metal body is heat$ x gets l>g] 9 e direction1 b if cool$ x returns to its orig9al size4 ,n[ if we make ! metal ( ! pi/on too ?ick s t ! wa/e heat _c pass quickly ?r\gh x & dissipate itself at cool] p>ts ( ! eng9e1 !n ! bulk ( ?is heat w be conc5trat$ 9 ! pi/on head1 caus+ x to exp& & become a tight fit 9 ! cyl9d]1 z ! cyl9d] walls are fairly ?9 & 9 contact ) ! jacket wat] :i* keeps !m fairly cool & prev5ts !m exp&+ mu* above _! normal size4 ,! actual am\nt ( expansion is v small ( c\rse1 b !re is v little cle>ance betwe5 ! pi/on & ! cyl9d] walls1 ev5 :5 ! eng9e is all cold--p]haps five-?\s&?s ( an in*4 ,! pi/on !re=e mu/ be /rong1 yet z light z we c make x1 hav+ reg>d to ! necessity = its be+ amply /iff & rigid & able to /& up to its "w4 ,illu/ration3 ,,fig4 #ae4--,,two ,,views ,,( ,a ,,ca/ ,,iron ,,pi/on ,,) ,,gudgeon ,,p9 ,,& ,,pack+ ,,r+s4 ,g5]ally x w be an iron ca/+ 9 ! =m ( a small cyl9d] 7see ,fig4 #ae71 hav+ provision 9 x = ! pack+ r+s ,p1 & ! gudgeon p9 ,g1 ) its fa/5+ screws ,s#a1 ,s#b4 ,! pi/on itself1 z we h obs]v$1 mu/ be a nice slid+ fit 9 ! bore ( ! cyl9d] )\t any %ake or side play :5 !re are no pack+ r+s 9 ! grooves4 ,! pack+ r+s are turn$ to size s z to fit ! cyl9d] exactly & prev5t any gas leak+ pa/ ! pi/on into ! crank*amb]4 ,^! r+s are v light1 are made f ca/ iron1 & arrang$ to break jo9t1 z indicat$1 by cutt+ ! middle r+ 9 ! opposite direction to ! two out] ones4 ,bosses are ca/ on ! inside ( ! pi/on & aft]w>ds bor$ out to receive ! /eel gudgeon p9 or wri/ p9 ,g4 ,?is p9 is be/ made ( pla9 p>allel cyl9drical =m gr\nd true1 & ! bosses 9 ! pi/on %\ld be ream]$ out to ! exact size ( ! p94 ,:5 ! p9 has be5 ins]t$ ! tap]$ screws are screw$ h>d up by means ( a special spann] & be> aga9/ ! p91 prev5t+ x f com+ loose or f %ak+ or knock+4 ,!re are _m o!r me?ods ( fix+ ! gudgeon p9 :i* are n %[n "h2 ea* has "s special po9t 9 its fav\r1 b ! "o illu/rat$ is und\bt$ly ! be/ & af=ds a positive adju/m5t = we>4 ,illu/ration3 ,,fig4 #af4--,,me?od ,,( ,,fix+ ,,! ,,gudgeon ,,p9 ,,:i* ,,all[s ,,= ,,adju/m5t ,,aft] ,,we>4 ,illu/ration3 ,,fig4 #ag4--,,?ree ,,=ms ,,( ,,pi/on ,,head4 ,an enl>g$ view ( "o ( ! bosses1 %[+ ! tap] p9 9 detail & h[ ! split p9 ,q prev5ts x f slack+ back by contact ) ! wall ( ! pi/on1 is %[n 9 ,fig4 #af4 ,sometimes ! l[] "p ( ! pi/on is made light] by drill+ holes ?r\gh ! walls4 ,x is v important to r$uce ! weight ( ! pi/on z mu* z possible1 o!rwise ! eng9e _c atta9 a high spe$1 s t x becomes ess5tial to be> ?is 9 m9d :5 con/ruct+ eng9es = rac+ purposes4 ,frequ5tly we f9d /eel pi/ons us$1 z !y may be made light] = ! same /r5g?1 & !n /eel pi/on r+s may be us$2 !y are n mu* 9 fav\r = ord9>y motor-c> eng9es because ! /eel pi/ons exp& at a great] rate ?an ! ca/ iron ( ! cyl9d]1 s t !re is m liability to seizure4 ,! cr[n ( ! pi/on is sometimes curv$ upw>ds & at o!r times curv$ d[nw>ds1 b m (t5 x is flat z %[n 9 ,fig4 #ag4 ,! gudgeon p9 is sometimes made ( mild /eel1 & ! surface is !n case-h>d5$ 9 ! c5tre :]e ! connect+ rod end be>s4 ,at ! pres5t "t x is q z common to f9d gudgeon p9s made ( special nickel /eel or o!r /eel alloys t d n require case-h>d5+4 ,on ! :ole ^! special /eels make ! be/ gudgeon p9s & /& ! h>de/ we>4 ,illu/ration3 ,,fig4 #ah4--;,,connect+ ,,rod ,,9 ,,! ,,=m ,,( ,a ,,phosphor ,,bronze ,,/amp+4 ,! ,connect+ ,rod is ano!r v important detail ( ! eng9e me*anism1 its function be+ to transmit ! =ce ( ! explosion f ! pi/on to ! crank%aft4 ,illu/ration3 ,,fig4 #ai4--,,/eel ,,connect+ ,,rod ,,turn$ ,,out ,,( ,,! ,,solid ,,b>4 ,"o end ( ! connect+ rod moves up & d[n ) ! pi/on & oscillates 7or sw+s to & fro7 on ! gudgeon p91 :ile ! o!r end ( ! connect+ rod travels 9 a circle1 be+ pivot$ at ! crankp9 & rotat+ 9 a circle :i* has = its c5tre ! c5tre l9e ( ! eng9e crank%aft4 ,?is is cle>ly indicat$ 9 ,fig4 #ah4 ,on ! suction /roke ( ! eng9e ! pi/on has to be pull$ d[n1 z we h already se52 on ! explosion /roke ! greate/ pressure acts on ! pi/on & pu%es ! connect+ rod d[n4 ,?us sometimes ! connect+ rod is be+ pull$ & at o!r times x is be+ pu%$2 9 ea* case x has to ov]come ! resi/ance ( ! eng9e & drive ! c>4 ,x is evid5t1 !re=e1 t ! "* ( ! load c>ri$ by a connect+ rod is j ab\t z complex & dang]\s z x is possible = a sy/em ( load+ to be1 & great c>e has to be tak5 9 ! design ( su* rods to ensure adequate /r5g? )\t undue weight1 z ?is w\ld t5d to keep d[n ! maximum spe$ ( ! eng9e4 ,ano!r important consid]ation is ! co/ ( production1 & = ?is reason "o (t5 f9ds x 9 ! =m ( a phosphor bronze /amp+ ( ,i section1 al?\gh ! ideal =m is a r\nd section ( /eel ) a /raight tap] f gudgeon p9 to crankp9 end1 & hav+ a hole bor$ "r up ! c5tre to r$uce ! weight )\t sacrific+ mu* /r5g?4 ,:5 ! rod is made 9 ! =m ( a /amp+ betwe5 dies x is possible to turn out great quantities at v l[ co/ & at a v rapid rate1 :]eas ! r\nd /eel rods w\ld require to be ma*9$ f ! solid b> to compete 9 price ) ! o!rs4 ,:5 phosphor bronze is us$ x is only necess>y to bore out c>efully & face ! be>+s at ! two ends = ! gudgeon p9 & crankp92 ! be>+ at ! crankp9 end is always =m$ ) a removable cap to facilitate fitt+ x nicely to ! crankp91 j\rnal & also to all[ = adju/m5t z ! be>+ we>s4 ,) /eel rods x is necess>y to ca/ a :ite-metal l9+ 9 ! crankp9 end & !n bore x out to =m ! be>+1 b ! cros%ead be>+ is usually =m$ by a phosphor bronze bu%4 ,x is evid5t1 !re=e1 t ! /eel rods are m exp5sive1 b !y make a spl5did me*anical job4 ,a /eel connect+ rod is %[n complete 9 ,fig4 #ai4 ,/amp$ /eel rods ( ,i section are also commonly us$ & are mu* bett] & /rong] ?an ^? made entirely ( phosphor bronze4 ,illu/ration3 ,,fig4 #bj4--;,,crankp9 ,,& ,,crankwebs4 ,illu/ration3 ,,fig4 #ba4--;,,f\r-,,?r[ ,,crank%aft ,! ,crank%aft1 z its "n implies1 is a %aft ) "o or m cranks or "r-angl$ b5ds 9 x4 ,its function is to conv]t ! slid+ motion ( ! pi/on into ! rot>y motion ( ! fly:eel & revolv+ %aft4 ,a crank%aft ) a s+le ?r[ 7or s+le crank7 is %[n 9 ,fig4 #bj2 a f\r-?r[ crank%aft is %[n 9 ,fig4 #ba2 & ,fig4 #bb %[s h[ an equival5t motion c be obta9$ by a s+le p9 fix$ into ! face ( a fly:eel4 ,?is device 7,fig4 #bb7 is frequ5tly us$ = motor-cycle eng9es4 ,crank%afts are always made ( /eel2 sometimes mild /eel is us$1 b m usually special alloys ( /eel conta9+ *rome1 nickel1 vanadium1 etc41 are us$4 ,! g5]al practice at ! pres5t "t is to ma*9e ! crank%aft direct out ( a solid b> ( /eel2 ?is requires special jigs = hold+ ! "w & special tools = cutt+ ! metal1 b is ! quicke/1 *eape/1 & mo/ satisfactory me?od to adopt4 ,a few firms specialize 9 ?is class ( "w ) high-grade /eel & c supply crank%afts f /ock4 ,illu/ration3 ,,fig4 #bb4--,,motor-,,cycle ,,crankp9 ,,fix$ ,,into ,,! ,,fly:eel4 ,x is easily se5 by exam9+ ,fig4 #ah t ! crank%aft is be+ twi/$ 9 ov]com+ ! eng9e resi/ance1 :ile ,fig4 #bj %[s t ! crank%aft is be+ b5t "u ! pu% f ! connect+ rod1 s t we say ! mat]ial ( a crank%aft is subject$ to comb9$ b5d+ & twi/+1 & z su* a comb9ation is n easy to resi/ we see n[ :y special /eel alloys are requir$ = safety1 comb9$ ) economy 9 mat]ial & r$uction ( weight4 ,9 ,fig4 #bj ! crankp9 is %[n at ,a1 ! crank *eeks or webs at ,b#a1 ,b#b & ! crank%aft prop] at ,c4 ,! portions ( ! crank%aft ,c :i* "w 9 ! be>+s ,d#a1 ,d#b are t]m$ j\rnals4 ,a crank%aft mu/ be v /iff & n b5d or twi/ s5sibly1 o!rwise ! %aft w vibrate :5 ! eng9e runs up to spe$--:i* w\ld be v undesirable4 ,x mu/ be p]fectly true ) all ! be>+s absolutely 9 l9e & ! j\rnals well b$d$ d[n 9 _! respective brasses 7or be>+s71 o!rwise me*anical tr\bles w arise4 ,ea* crank ) its crankp9 & webs =ms a lop-sid$ or unbalanc$ mass1 s t ei!r 7#a7 ea* crank mu/ h its own balance weight z 9 ,fig4 #bc1 or 7#b7 special balanc+ masses mu/ be fitt$ at ea* end ( ! crank%aft4 ,a conv5i5t me?od ( balanc+ ! crank%aft is to h a fan pulley at "o end & ! fly:eel at ! opposite end1 s t by drill+ holes 9 ! faces ( ^! discs an am\nt ( metal may be remov$ f !m suffici5t to balance ! excess weight ( ! respective crankp9s & webs4 ,9 ,fig4 #bd ! %ad$ area indicates t portion ( ! crank :i* con/itutes an unbalanc$ mass4 ,crank%afts = high-spe$ eng9es h always to be v c>efully balanc$1 o!rwise ! eng9es w nev] run satisfactorily1 ! want ( balance be+ greatly aggravat$ z ! spe$ ( rotation increases4 ,fig4 #be %[s h[ ! crank%aft ( a two-cyl9d] eng9e may be balanc$ by drill+ holes 9 ! fly:eel & fan pulley respectively1 b ! same effect may be produc$ by atta*+ balanc+ masses--?is latt] me?od w\ld1 h[ev]1 be m inconv5i5t & exp5sive4 ,! crankp9s & j\rnals are gr\nd truly circul> aft] be+ turn$ 9 ! la! z true z possible4 ,illu/ration3 ,,fig4 #bc4--,,sket* ,,( ,a ,,balanc$ ,,crank4 ,illu/ration3 ,,fig4 #bd4--,,sket* ,,%[+ ,,! ,,unbalanc$ ,,portion ,,( ,,! ,,crank ,,by ,,%ad$ ,,l9es4 ,illu/ration3 ,,fig4 #be4--,,two-,,?r[ ,,crank%aft ,,balanc$ ,,by ,,drill+ ,,holes ,,9 ,,fly:eel ,,& ,,fan ,,pulley4 ,illu/ration3 ,,fig4 #bf4--,,sket* ,,to ,,illu/rate ,,! ,,=ces ,,act+ ,,on ,a ,,fly:eel ,,rim4 ,! ,fly:eel4--,we h already describ$ h[ ! =ce driv+ ! pi/on ( a motor-c> eng9e v>ies dur+ ! f\r /rokes ( ! cycle1 b we mu/ note t x also v>ies consid]ably dur+ ea* individual /roke4 ,?us1 on :at is kn[n z ! explosion /roke 7or p[] /roke7 ( ! cycle1 ! pressure at ! comm5cem5t ( ?is /roke may be exce$+ly great & yet t[>ds ! end ( ! /roke ! gases h exp&$ & ! exhau/ valve has be5 op5$1 s t ! pressure act+ on ! pi/on is !n v small4 ,aga91 on ! compression1 suction1 & exhau/ /rokes1 ! pi/on has to be pu%$ or pull$ by "s means1 z no p[] is be+ g5]at$4 ,!re=e1 if ! eng9e is to be self-act+ & run cont9u\sly1 "s means mu/ be provid$ = /or+ up ! great =ce ( ! explosions & giv+ x out aga9 on ! idle /rokes4 ,! function ( ! fly:eel is to /ore any en]gy giv5 to x ov] & above t requir$ to drive ! c> & to give x out aga9 :5 requir$ = p]=m+ ! functions ( compress+1 exhau/+1 & suck+ 9 gas1 z well z to keep ! c> runn+ /eadily4 ,x is simply a heavy :eel m\nt$ on ! end ( ! crank%aft :i*1 :5 once />t$ revolv+ at a high spe$1 is n easily /opp$1 & :i* w give up "p ( its en]gy ea* "t its spe$ is r$uc$ ow+ to ! dem&s ( ! eng9e2 b :5 ! eng9e is g5]at+ p[] ! :eel w spe$ up & /ore ! excess--! m]e fact t ! :eel is heavy causes ^! *anges 9 spe$ to occur sl[ly1 & !re=e on ! :ole ! fluctuation ( spe$ is n great :5 a suitable fly:eel is fitt$4 ,! fly:eel does n limit ! maximum spe$ ( ! eng9e1 z x c\ld g on sl[ly increas+ 9 spe$ if no resi/ance 0 enc\nt]$ until ! :eel f9ally bur/ or flew to pieces4 ,?us ! fly:eel does n regulate ! spe$ ( ! eng9e2 x m]ely smoo?s out ! inequalities 9 ! sev]al /rokes ( ! 8cycle40 ,fly:eels ( motor-c> eng9es are n[ always made ( /eel1 s t !y c be safely run at spe$s up to #c1jjj revolutions p] m9ute )\t fe> ( ! rim bur/+4 ,all p>ts ( ! rim t5d to fly (f radially 9 ! direction ( ! arr[s z %[n 9 ,fig4 #bf "u ! action ( c5trifugal =ce4 ,a built-up fly:eel is %[n 9 ,fig4 #bg1 & "o made f a s+le /amp+ ( /eel is %[n 9 ,fig4 #bh4 ,g5]ally speak+1 :5 a con$ clut* is fitt$ "o portion ( x is =m$ on ! inside ( ! fly:eel rim z indicat$ 9 ^! two figures4 ,:5 ! con/ruction %[n 9 ,fig4 #bh is adopt$ ! l9+ w\ld be ins]t$ aft] ! clut* cone _h be5 put into place2 v (t5 ! l9+ is made up ( sections :i* c be readily ins]t$ or )drawn aft] ! cone is 9 position4 ,illu/ration3 ,,fig4 #bg4--;,a ,,fly:eel ,,built ,,up ,,f ,,/eel ,,=g+s4 ,illu/ration3 ,,fig4 #bh4--;,a ,,fly:eel ,,turn$ ,,f ,a ,,/eel ,,/amp+4 ,,*apt] ,,iv ,,! ,,valves ,poppet ,valves4--,valves are provid$ = ! purpose ( controll+ ! admission ( ! mixture to ! cyl9d] & also = controll+ ! exhau/ or ejection ( ! burnt gases at ! end ( ! fir+ /roke4 ,! mo/ common =m ( valve is ! mu%room or poppet type ( valve %[n 9 ,fig4 #bi1 9 :i* ,a is ! valve head1 ,b is ! valve /em1 ,c is ! valve seat+1 & ,d is ! cott] hole = ! cott] ,e4 ,x w be se5 t ! g5]al appe>ance ( ! valve is a disc ( /eel ) a f9e /em to x simil> to a mu%room 9 g5]al outl9e--h5ce its "n4 ,! valve has a con$ face :i* is kept press$ d[n on a con$ seat+ by means ( ! pressure ( a p[]ful spr+ ,f act+ on ! wa%] ,g1 :i* be>s aga9/ ! cott] ,e & ?us presses d[n ! valve /em4 ,to ensure t ! valve %all always come d[n correctly on its seat+ & make a gas-tight jo9t1 ! valve /em guide ,m is provid$4 ,illu/ration3 ,,fig4 #bi4--;,,g5]al ,,arrangem5t ,,( ,a ,,poppet ,,valve 7,a7 ,,) ,,tappet 7,k7 ,,& ,,cam 7,h74 ,! cam ,h raises ! valve (f its seat at ! requir$ in/ant :5 ! motion ( ! cam%aft br+s ! cam "u ! roll] ,r4 ,! cam lifts ! roll] v]tically & ) x ! tappet or pu% rod ,k1 :i* slides v]tically upw>ds 9 ! guide ,p & lifts ! valve4 ,! tappet is provid$ ) an adju/able head ,s kept 9 position by ! locknut ,t4 ,to adju/ ! cle>ance betwe5 ! head ( ! tappet & ! und]side ( ! valve /em ! locknut ,t mu/ fir/ be slack5$ back & !n ! head ,s c be screw$ up or d[n z desir$1 ! be/ cle>ance be+ ab\t #a_/fd ( an in*2 ! locknut is !n tight5$ d[n aga94 ,dur+ ?is op]ation ! valve mu/ be d[n on its seat4 ,sometimes to r$uce ! noise aris+ f ! tappet /rik+ ! valve /em1 ! head ( ! tappet is padd$ ) "s mat]ial su* z h>d vulcanite fibre1 b ?is we>s d[n m quickly ?an /eel & requires frequ5t adju/m5t4 ,! late/ device = r$uc+ ! noise aris+ f ! valve me*anism consi/s 9 totally enclos+ ! valve ge> & spr+s ei!r by metal plates bolt$ to ! cyl9d] ca/+ or by ext5d+ ! crank*amb] to cov] x all 91 & !n x is c]ta9 to be well lubricat$4 ,! exhau/ valve is always liable to give tr\ble ei!r f leakage or seizure or o!r causes due to ! great heat ( ! exhau/ gases1 s t ! valves are (t5 made n[ ( tung/5 /eel alloy :i* is n mu* affect$ by heat4 ,if a mu%room type valve leaks x c be gr\nd 9 & made a tight fit on its seat+1 provision usually be+ made = ?is 9 ! =m ( a slot cut 9 ! valve head1 z %[n 9 ,fig4 #cb1 = ! ins]tion ( a screwdriv] or special tool4 ,to gr9d 9 a valve1 remove ! cap ,q by unscrew+ x1 raise ! spr+ ,f by pu%+ up ! wa%] ,g & !n )draw ! cott] ,e4 ,lift out ! valve & sme> ! con$ face ) f9e em]y p[d] & oil 7or wat]74 ,put ! valve back & turn x to & fro on its seat+ by means ( ! screwdriv]1 keep+ a firm pressure d[n on x2 cont9ue ! op]ation until by exam9+ ! valve y asc]ta9 t x t\*es on ! seat+ all ! way r\nd1 !n c\ple up ! spr+ aga91 aft] c>efully remov+ all traces ( ! em]y p[d]4 ,illu/ration3 ,,fig4 #cj4--,,sectional ,,draw+ ,,( ,,! ,,cyl9d] ,,( ,a ,,sleeve ,,valve ,,eng9e1 ,,) ,,inlet ,,=ts ,,uncov]$4 ,illu/ration3 ,,fig4 #ca4--,,sectional ,,draw+ ,,( ,,! ,,cyl9d] ,,( ,a ,,sleeve ,,valve ,,eng9e1 ,,) ,,exhau/ ,,ports ,,uncov]$4 ,sleeve ,valves4--,ano!r =m ( valve :i* has come v mu* into fav\r is ! sleeve valve1 two views ( :i* are %[n 9 ,figs4 #cj & #ca4 ,9 ?is case ! gases ent] ! cyl9d] ?r\gh ports or slots ,p cut 9 ! cyl9drical ca/ iron sleeves ,s#a1 ,s#b1 :i* are plac$ betwe5 ! pi/on ,k & ! walls ( ! wat]-jacket$ cyl9d] ,c4 ,^! sleeves are mov$ up & d[n inside ! cyl9d]1 :ile ! pi/on travels up & d[n inside ! inn] sleeve ,s#b j z ?\gh x con/itut$ ! cyl9d] ,c4 ,"s eng9es h two sleeves1 z %[n 9 ! figure1 b o!rs h only "o sleeve1 & !re is v little to *oose betwe5 ! two types on ! score ( effici5cy4 ,! great claim made = ! sleeve valve is t x is almo/ noiseless 9 action & gives v mu* full] op5+s = inlet & outlet ( ! gases4 ,! pi/on has ! usual numb] ( pack+ r+s to keep x gas-tight1 & !re is also a deep pack+ r+ provid$ 9 ! head ( ! cyl9d] ,h to keep ! sleeve ,s#b gas-tight & prev5t loss ( compression pressure4 ,! head ( ! cyl9d] is usually deta*able1 & has (t5 sep>ate wat] connexions 9 ! =m ( pipes lead+ f ! cyl9d] jackets4 ,! sleeves receive _! reciprocat+ motion f ecc5trics & rods atta*$ to p9s %[n at ! bottom "r-h& corn] ( ea* sleeve4 ,x might be expect$ t ! sleeves w\ld get v hot or v dry & seize up1 or ! pi/on might seize1 b 9 actual practice ?is has n occurr$ to any great ext5t1 & on ! :ole !y h be5 v successful4 ,x is1 h[ev]1 necess>y to keep ! eng9e well lubricat$1 especially :5 ! sleeves get worn1 z ! oil prev5ts loss ( gas by leakage pa/ ! sleeves & pi/on4 ,9 ,fig4 #ca ! two sleeves h come toge!r 9 su* a position t ! ports co9cide ) ! exhau/ ports cut 9 ! cyl9d] walls & !re=e ! exhau/ is full op51 & z ! sleeves travel at times 9 opposite directions quick op5+ & clos+ ( ! ports is secur$4 ,! cyl9d] head is held d[n to ! cyl9d] ca/+ by screws or bolts & c be readily deta*$ = clean+ or inspect+ ! int]ior ( ! cyl9d]4 ,! great objection rais$ aga9/ ! sleeve valves is _! excessive weight & ! unme*anical mann] 9 :i* !y are op]at$4 ,illu/ration3 ,,fig4 #cb4--,,sket* ,,%[+ ,,slot ,,9 ,a ,,poppet ,,valve ,,head ,,= ,,gr9d+-,,9 ,,purposes4 ,illu/ration3 ,,fig4 #cc4--;,,inlet 7,a7 ,,& ,,exhau/ 7,b7 ,,valve ,,cams ,,= ,a ,,sl[-,,runn+ ,,petrol ,,eng9e4 ,! ,cam%afts & ,ecc5tric ,%afts4--,^! are usually made f ! same mat]ial z ! crank%aft & ma*9$ f ! solid b>1 ! project+ cams or ecc5trics be+ aft]w>ds cut to ! correct %ape4 ,9 ! case ( a cam%aft x is v important t ! %ape ( ! cams %\ld be su* t !y lift ! valves quickly (f _! seats to ! full ext5t ( _! op5+ 7or lift71 keep !m op5 = z long a p]iod z desirable1 & !n all[ !m to close quickly b )\t %ock4 ,cams :i* h /raight sides are m 9 fav\r ?an ^? ) curv$ sides1 b if ! action ( ! cams is to be !oretically correct ! side ( ! cam %\ld be curv$ 9 su* a mann] t ! valve is lift$ at fir/ ) a uni=mly increas+ spe$ & aft]w>ds ) a uni=mly decreas+ spe$1 s t x w be at re/ 9 its top position4 ,if ?is is n done ! valve tappet may jump a little above ! cam ea* "t ! valve is lift$4 ,9 ,fig4 #cc ! cam ,a is int5d$ = ! inlet valve & ! cam ,b = ! exhau/ valve1 ! ess5tial diff]5ce be+ t ! exhau/ valve mu/ be kept op5 long] ?an ! inlet valve1 & !re=e ! exhau/ valve cam is ! wid] ( ! two4 ,! tim+ ( ! inlet & exhau/ valves ( an up-to-date eng9e may be expla9$ by consid]+ ! crankp9 circle z divid$ into #cfj p>ts or degrees4 ,if !re 7 no lag or lead 9 ! op5+ ( ! valves1 !n !y w\ld op5 :5 ! crank 0 on its dead-c5tre & close :5 ! crank 0 on its dead-c5tre4 ,! inlet valve w\ld op5 :5 ! crank 0 on its top dead-c5tre & close :5 x _h rea*$ its bottom dead-c5tre1 ?is repres5t+ ! suction /roke ( ! eng9e4 ,!n w\ld foll[ compression & explosion1 giv+ two /rokes or "o revolution be=e ! exhau/ valve comm5c$ to op54 ,! exhau/ valve w\ld !n op5 :5 ! crank 0 on its bottom dead-c5tre & close :5 ! crank rea*$ its top dead-c5tre correspond+ to ! completion ( ! exhau/ /roke4 ,x is v important t ! pressure ( ! gases above ! pi/on :5 x comm5ces to move upw>ds on ! exhau/ /roke %\ld be z l[ z possible1 & ?is c only be secur$ by op5+ ! exhau/ valve t[>ds ! end ( ! explosion or p[] /roke1 ?us all[+ ! bulk ( ! gases to escape & leav+ ! pi/on ) little resi/ance to enc\nt] on its upw>d exhau/ /roke4 ,!re=e we give ! exhau/ valve a lead ( ab\t #cj degrees1 :i* means t x beg9s to op5 :5 ! eng9e crank is #cj degrees f ! bottom dead-c5tre on ! d[nw>d explosion /roke1 & we give x a lag ( ab\t #e degrees 9 clos+4 ,?is means t we keep ! exhau/ valve op5 until ! crank has mov$ #e degrees ov] ! top c5tre1 s t we may fully utilize ! mom5tum ( ! gases to cle> out ! cyl9d] or scav5ge x4 ,z ! pi/on moves rapidly up ! cyl9d] on ! exhau/ /roke x pu%es ! gases 9 front ( x out ?r\gh ! exhau/ op5+1 b :5 x gets to ! top ( its /roke ! pi/on /ops & !n comes d[n aga9 = ! suction /roke1 :]eas ! gases w t5d to keep on mov+ if !y are n unduly re/rict$ 9 _! passage ?r\gh ! exhau/ sy/em1 s t we c g5]ally obta9 "s slight advantage by giv+ ! exhau/ valve a small am\nt ( lag 9 clos+4 ,! pressure ( ! gases 9 ! cyl9d] aft] ! exhau/ valve closes w ne>ly always be a little above atmosph]ic pressure1 & !re=e no?+ is ga9$ by op5+ ! inlet valve imm$iately ! exhau/ closes--we g5]ally all[ an int]val ( #e degrees1 :i* means t ! total lag ( ! inlet valve is #aj degrees 9 op5+1 or ! inlet valve does n beg9 to op5 until ! crank has mov$ #aj degrees (f its top dead-c5tre on ! d[nw>d suction /roke4 ,at ! end ( ! suction /roke ! pi/on w aga9 come to re/ be=e mov+ up on ! compression /roke1 b ! gases w cont9ue to ru% into ! cyl9d] f ! c>burettor ow+ to _! mom5tum if we leave ! inlet valve op5 a little long]1 h5ce we g5]ally give x a lag ( #bj degrees 9 clos+1 :i* means t ! inlet valve does n close until ! crank has mov$ #bj degrees up f ! bottom dead-c5tre on ! compression /roke4 ,illu/ration3 ,,fig4 #cd4--;,,ecc5tric ,,%eave 7,a7 ,,& ,,ecc5tric ,,rod 7,b7 ,,= ,,op]at+ ,a ,,sleeve ,,valve4 ,! cam%aft requires to be well support$ 9 be>+s to prev5t x f sagg+ or b5d+ "u its load4 ,if ! %aft & ! cams are n made f nickel /eel or high-grade /eel alloy1 !y require to be case-h>d5$ 7h>d5$ on ! surface7 to prev5t we> on ! surfaces due to ! pressure ( ! valve spr+s1 :i* is consid]able & may rea* #ajj lb4 p] valve easily2 ! same applies to ! roll]s ( ! tappets4 ,:5 sleeve valves are fitt$ to ! eng9e1 ecc5tric %eaves mu/ be us$ in/ead ( cams1 z no spr+s are employ$4 ,an ecc5tric %eave ) its /rap & rod are %[n 9 ,fig4 #cd4 ,! valve %aft or lay %aft is %[n at ,c1 & ! %eave ) ! hole bor$ ecc5trically is %[n at ,a1 & ,b is ! comb9$ ecc5tric /rap & rod4 ,! p9 ,d op]ates ! sleeve valve1 giv+ x a reciprocat+ motion 9 a v]tical direction1 ! angul> movem5t be+ tak5 up by ! oscillation ( ! rod ab\t ! p9 ,d1 :i* w\ld be fix$ into ! sleeve4 ,sometimes a groove is =m$ r\nd ! p]iph]y ( ! ecc5tric disc or %eave to keep ! /rap 9 position & prev5t end movem5t4 ,z ! weight ( ! sleeves is v consid]able1 ! p9 ,d & ! ecc5tric rod mu/ be well proportion$ to prev5t breakage or undue we>4 ,illu/ration3 ,,fig4 #ce4--;,a ,,pair ,,( ,,tim+ ,,:eels4 ,! ,tim+ ,:eels4--,z !re is only "o suction /roke & "o exhau/ /roke 9 e two revolutions ( ! eng9e crank%aft1 x w be cle> t ! cam%aft or ecc5tric %aft mu/ be driv5 at half ! spe$ ( ! eng9e crank%aft4 ,?is may be done by ! use ( two ge> :eels or :eels hav+ tee? cut on _! p]iph]y1 su* :eels :5 us$ = ?is purpose be+ call$ tim+ :eels1 because ! positions ( ! cams on ! cam%aft 7or ! ecc5trics on ! ecc5tric %aft7 relative to ! eng9e crank%aft :5 ! tee? ( ! tim+ :eels are put into me% det]m9es ! tim+ ( ! inlet & exhau/ valves1 i4e41 ! in/ant at :i* !y w op5 or close4 ,a pair ( tim+ :eels is %[n 9 ,fig4 #ce4 ,! p9ion ,a has twelve tee? & is key$ to ! eng9e crank%aft1 b ! :eel ,b1 :i* is key$ to ! valve %aft1 has tw5ty-f\r tee?1 & h5ce ! valve %aft runs at half ! spe$ ( ! crank%aft4 ,! :eels %[n are spur ge>s1 & ! tee? run /raight across ! rim ( ! :eel2 x is1 h[ev]1 q common to f9d :eels ) curv$ or helical tee?1 z ^! run quiet]4 ,sometimes :5 spur ge>+ is us$1 "o ( ! :eels is made ( fibre & ! o!r ( /eel1 b :5 helical ge>s are us$ ! :eels are g5]ally made f nickel /eel ( high t5sile /r5g?4 ,! f9] ! pit* ( ! tee? 7i4e4 ! di/ance betwe5 ! c5tres ( consecutive tee?7 ! quiet] ! ge>s w run1 b ! "q ( /r5g? & ! co/ ( production mu/ also be consid]$4 ,! late/ practice is to use a sil5t *a9 drive2 ?is orig9at$ ) ! introduction ( ! sleeve valve & ecc5tric %aft4 ,:5 *a9s are us$ = ! tim+ :eels provision mu/ be made = tak+ up slack 9 ! *a9 ow+ to /ret*+ ( ! l9ks1 & z ?is _c be done 9 ! usual mann] 7by slid+ ! sprocket :eels fur!r ap>t7 ow+ to ! c5tres ( ! crank%aft & ! valve %aft be+ rigidly fix$ by ! be>+s1 a small jockey pulley 7) tee? on x simil> to ^? on ! *a9 sprocket :eels7 is provid$ atta*$ to a %ort %aft or sp9dle1 :i* c be rais$ or l[]$ at w1 & ?us keep ! correct t5sion on ! *a94 ,! *a9 drive mu/ be m exp5sive & require m att5tion2 moreov]1 x _c be s v mu* quiet] 9 action ?an good well-cut helical ge>+4 ,illu/ration3 ,,fig4 #cf4 ,illu/ration3 ,,fig4 #cg4 ,,two ,,views ,,( ,a ,,crank*amb]4 ,! ,crank*amb]4--,! crank*amb]1 z its "n implies1 is ! receptacle :i* conta9s & supports ! crank%aft & also ! cam%aft4 ,x is g5]ally an alum9ium ca/+1 b frequ5tly = comm]cial vehicle eng9es ! top portion is made ( ca/ iron & ! bottom portion ( %eet /eel4 ,9 ei!r case brass or gunmetal be>+s1 (t5 l9$ ) :ite metal1 are fitt$ = ! %afts to revolve 91 & ! eng9e cyl9d]s are m\nt$ on ! top ( ! *amb]4 ,provision %\ld be made on ! sides & ends ( ! crank*amb] = fitt+ ! magneto & oil pump & also ! wat] pump1 if requir$4 ,!re mu/ also be "s =m ( h\s+ or ext5sion ( ! *amb] to enclose ! tim+ :eels1 & sometimes ! :ole ( ! valve ge> is conta9$ )9 ! crank*amb] to ensure prop] lubrication = x & /op any noise f x rea*+ ! outside _w4 ,x is also important t !re %\ld be l>ge inspection op5+s fitt$ ) prop] oil-tight cov]s & "s provision = easily p\r+ l>ge quantities ( oil d[n into ! l[] portion ( ! *amb]4 ,! design ( a crank*amb] necessitates c>eful =e?\ght to ensure ample provision = all ! necess>y atta*m5ts & fitt+s & to secure ! maximum accessibility ( all p>ts4 ,"o or two v5t pipes1 consi/+ ( upw>dly project+ pipes hav+ _! out] end cov]$ ) wire gauze & scre5$ f du/ %\ld be provid$ to all[ hot air & gas to escape f ! *amb]4 ,two views ( a crank*amb] ( mod]n design are %[n 9 ,figs4 #cf & #cg4 ,9 ^! figures ,a is ! top half ( ! crank*amb] :i* re/s ^u ! *assis or framework ( ! c>1 be+ bolt$ to an und]frame at ,b & ,c4 ,! cyl9d]s are atta*$ to ! *amb] at ! flange ,h by means ( /uds & nuts4 ,?is portion1 ! top half ( ! crank*amb]1 requires to be v /rong & /iff1 because ! upw>d pressure ( ! explosions acts on ! cr[n ( ! cyl9d] & t5ds to te> ! cyl9d] (f ! flange ,h1 :ile at ! same "t x ex]ts a great =ce on ! pi/on1 pu%+ x d[nw>ds & t5d+ to =ce ! crank%aft d[n out ( its be>+s4 ,9 ! be/ practice ! :ole weight ( ! crank%aft is support$ f ! top half ( ! crank*amb] & is c>ri$ on ! be>+ bolts z %[n at ,s1 s t !y also receive ! d[nw>d ?ru/ ( ! pi/on & 9 _! turn transmit x to ! ma9 ca/+4 ,! bottom half ( ! crank*amb] !n becomes m]ely an oil conta9]1 or res]voir1 & du/ cov]2 x %\ld be s arrang$ & situat$ t x may be readily remov$ = inspection ( %aft & be>+s f und]nea?4 ,sometimes ! crank*amb] has long arms1 :i* c be atta*$ directly to ! side memb]s ( ! *assis1 or x may be support$ 9 ! *assis by a tubul> cross memb]4 ,9 ,fig4 #cg ! cam%aft is %[n at ,t2 ! magneto w\ld be c>ri$ on ! bracket ,e & driv5 by ge>+ f ! crank%aft4 ,! fac+ at ,g is = ! wat] pump1 :i*1 9 ?is case1 is int5d$ to be m\nt$ on an ext5sion ( ! cam%aft ,t4 ,! oil pump w\ld be fix$ at ,f1 pref]ably t[>ds ! re> ( ! eng9e1 s z to secure an adequate supply ( oil = ! pump :5 ! c> is climb+ a /eep hill4 ,! oil c\ld be drawn (f & ! res]voir empti$ by unscrew+ ! l>ge plug %[n 9 ! c5tre ( ,d 9 ,fig4 #cg4 ,! tim+ :eel h\s+ or cas+ is %[n at ,q2 ! oil ducts & connexions = supply+ ! ma9 be>+s ) oil are n %[n 9 ^! draw+s1 nor are ! inspection op5+s & cov]s4 ,! upp] half ( ! crank*amb] frequ5tly becomes v hot1 due to conduction ( heat f ! metal ( ! cyl9d]s1 & = ?is reason x has f "t to "t be5 propos$ to draw ! air supply ( ! c>burettor ?r\gh ! crank*amb] to s]ve ! dual purpose ( cool+ ! be>+s & heat+ ! air supply to ! c>burettor2 b ! idea has n f\nd fav\r1 z !re is consid]able risk ( du/ & grit f9d+ its way into ! be>+s & caus+ tr\ble due to abrasion4 ,,*apt] ,v ,,! ,,c>burettor ,,& ,,c>buration ,a c>burettor is a contrivance = supply+ an explosive mixture ( air & petrol vap\r to a petrol eng9e4 ,petrol1 al?\gh a liquid fuel1 is a comb9ation ( c>bon & hydrog5 :i*1 :5 suppli$ ) ! necess>y air1 c be burnt & ?us evolve heat1 :i* heat is turn$ into "w inside ! eng9e cyl9d]4 ,:at we h to supply to ! eng9e is really a mixture ( air & petrol vap\r 9 c]ta9 proportions1 su* a mixture be+ (t5 spok5 ( z c>burett$ air on acc\nt ( ! c>bon conta9$ 9 x4 ,ab\t two p>ts ( petrol vap\r 7by volume7 are requir$ to e "o hundr$ p>ts ( mixture1 or fifte5 p\nds ( air to e p\nd ( petrol vap\r 7by weight74 ,?is c>burett$ air mu/ be ( ! requir$ /r5g? & =m a homog5e\s mixture 9 ! =m ( a vap\r4 ,! problem ( c>buration consi/s 9 =m+ a mixture ( ! correct /r5g? & "*4 ,air may be c>burett$ by pass+ x ov] ! surface ( liquid petrol 9 a surface c>burettor1 or by draw+ x ov] or among wicks saturat$ ) liquid petrol z 9 ! wick type ( c>burettor1 b bo? ^! me?ods h be5 l>gely sup]s$$ by ! use ( :at is n[ kn[n z a jet or spray type ( c>burettor1 9 :i* ! petrol is spray$ f a f9e jet & mixes ) air :i* is pass+ up rapidly r\nd ! outside ( ! jet4 ,9 all cases1 h[ev]1 ! liquid petrol mu/ be vaporiz$ be=e ent]+ ! eng9e1 & to d ?is heat mu/ be suppli$ to ! mixture1 j z wat] has to be heat$ be=e x c be vaporiz$ & turn$ into /eam4 ,"u ord9>y circum/ances suffici5t heat c be obta9$ f ! incom+ air to effect vaporization ( ! liquid petrol if x issues 9 ! =m ( a v f9ely divid$ spray1 b :5 ! dem& = mixture1 f ! eng9e1 is great ! air _c supply ! requisite heat )\t its temp]ature fall+ bel[ ! vaporization po9t2 h5ce mo/ c>burettors ( up-to-date patt]n are fitt$ ) a mix+ *amb] surr\nd$ by a hot-wat] jacket4 ,! ess5tial features ( ! c>burett+ plant are %[n diagrammatically 9 ,fig4 #ch1 9 :i* ,a is ! petrol tank fitt$ ) ! petrol tap ,g1 to :i* is c\pl$ ! petrol pipe ,f4 ,"s =m ( petrol filt] z indicat$ at ,b %\ld be plac$ betwe5 ! tank & ! c>burettor ,c4 ,! ?rottle valve ( ! c>burettor is %[n at ,h1 ! extra-air valve at ,e1 & ! eng9e induction pipe at ,d4 ,illu/ration3 ,,fig4 #ch4--;,,g5]al ,,arrangem5t ,,( ,,! ,,c>burett+ ,,plant1 ,,%[+ ,,petrol ,,tank 7,a71 ,,petrol ,,filt] 7,b71 ,,c>burettor 7,c71 ,,& ,,extra-,,air ,,valve 7,e74 ,! c>burettor prop] may be con/ruct$ 9 a v>iety ( =ms1 b ! elem5ts ( :i* x is compos$ are3 7#a7 ! float *amb] ,a1 7#b7 ! petrol jet ,b1 7#c7 ! *oke tube ,c1 7#d7 ! mix+ *amb] ,d1 & 7#e7 ! ?rottle valve ,e1 z %[n 9 ,fig4 #ci4 ,illu/ration3 ,,fig4 #ci4--,,sectional ,,draw+ ,,( ,a ,,c>burettor ,,( ,,! ,,jet ,,type4 ,! ,float ,*amb] is g5]ally cyl9drical 9 =m & ! liquid ent]s at ! bottom1 ! fl[ be+ regulat$ by a po9t$ rod call$ a ne$le valve4 ,a holl[ metal float :i* c slide freely up & d[n ! ne$le valve /em op]ates two lev]s :i* are pivot$ on ! float *amb] cov]4 ,x is well kn[n t :5 a body is imm]s$ 9 a liquid ! liquid ex]ts an upw>d pressure on ! body equal to ! weight ( liquid displac$ by ! body4 ,! float be+ holl[ & made ( v ?9 %eet metal1 displaces a v l>ge quantity ( liquid 9 proportion to its own weight1 & is !re=e v buoyant4 ,! buoyancy ( ! float w1 ( c\rse1 dep5d on ! d5sity ( ! liquid 9 ! float *amb]1 & x w naturally s9k deep] d[n into petrol ?an x w\ld into a heavi] _s su* z p>aff9 or b5zol4 ,! action ( ! float is z foll[s3--,suppos+ ! petrol to be turn$ (f & ! ne$le valve lift$ up (f its seat+1 !n on turn+ on ! petrol supply ! petrol w run into ! float *amb]1 & z ! level ( ! liquid rises ! float w rise too1 lift+ up ! out] ends ( ! lev]s & depress+ ! ne$le valve d[n on to its seat+ by means ( ! coll> :i* is rigidly atta*$ to ! sp9dle ( ! ne$le valve4 ,if at any "t ! level ( ! liquid 9 ! *amb] falls1 ! float w fall also1 ?us all[+ ! out] ends ( ! lev]s to drop & raise up ! ne$le valve f its seat+2 ?is all[s m petrol to ent] ! *amb] & raises ! float aga91 ?us keep+ a con/ant level 9 ! *amb]4 ,! height ( ! orifice 9 ! top ( ! petrol jet above ! bottom ( ! float *amb] det]m9es ! height at :i* we require ! liquid to /& 9 ! *amb]4 ,z a g5]al rule ! level ( ! liquid 9 ! float *amb] %\ld be slightly bel[ ! top ( ! jet orifice to prev5t ! liquid ooz+ ov] & caus+ flood+ or cont9u\s dripp+ ( petrol f ! jet1 ev5 :5 ! eng9e is n runn+4 ,! height ( ! coll> on ! ne$le valve sp9dle mu/ be adju/$ until ! float closes ! valve d[n on its seat+ :5 ! liquid has ris5 to ! desir$ height 9 ! float *amb]4 ,h5ce1 if a c>burettor has be5 adju/$ to "w ) petrol1 x w require to h "s slight extra weight add$ to ! float :5 work+ ) heavi] spirits to cause x to s9k to ! requir$ dep? 9 ^! d5s] spirits4 ,! ,petrol ,jet & ,*oke ,tube4--,! petrol jet g5]ally consi/s ( a %ort tube ( f9e bore1 "o end ( :i* conta9s a v small orifice = ! purpose ( spray+ ! petrol into ! *oke tube4 ,:5 ! eng9e is at re/ x is easily se5 t ! pressure ( ! air 9 ! *oke tube is atmosph]ic1 & t ! pressure above ! liquid 9 ! float *amb] is also atmosph]ic1 b :5 ! eng9e is runn+ x draws air up ! *oke tube at a v high spe$ & ?us causes a p>tial vacuum r\nd ! petrol jet1 & !re=e ! petrol spurts out ( ! jet "u ! pressure diff]5ce :i* !n exi/s & issues 9 ! =m ( a f9e spray :i* is readily vaporiz$4 ,! *oke tube is purposely made ( r small diamet]1 9 ord] to get a high air spe$1 :i* results 9 a l[ pressure r\nd ! jet & ensures a good driv+ =ce to spray ! petrol out ( ! jet4 ,! spe$ ( ! eng9e is controll$ by ! position ( ! ?rottle valve or disc ,e1 :i* regulates ! am\nt ( air fl[+ up ! *oke tube1 & !re=e incid5tally *ecks ! quantity ( petrol issu+ f ! jet by regulat+ ! vacuum 9 ! neighb\rhood ( ! jet orifice4 ,at l[ eng9e spe$s !re is v little suction or vacuum effect on ! jet1 b at high eng9e spe$s ) full ?rottle op5+ ! maximum suction ( ! eng9e is ex]t$ ^u ! jet4 ,?us at l[ spe$s ) ?is type ( c>burettor we d n get en\gh petrol out ( ! jet1 & at high spe$s we get too mu*1 :i* results 9 too weak a mixture at l[ spe$s & too ri* a mixture at high spe$s4 ,"o reason = ?is is t ! air fl[s out ( ! *oke tube fa/] ?an x fl[s into x1 ow+ to ! fact t its volume increases z ! pressure decreases1 & h5ce ! pressure r\nd ! jet falls v rapidly inde$ z ! air velocity increases & causes too mu* petrol to issue f ! jet 9 proportion to ! quantity ( air fl[+ ?r\gh ! tube4 ,! *oke tube is (t5 a pla9 piece ( pipe1 z %[n 9 ,fig4 #dj1 in/ead ( be+ tap]$ z 9 ,fig4 #ci4 ,! ,mix+ ,*amb] & ,?rottle ,valve4--,! ?rottle valve is usually a pla9 flat disc ( metal m\nt$ on a sp9dle :i* c be rotat$ & ?us regulate ! size ( ! air passage to ! eng9e4 ,x is plac$ above ! petrol jet & situat$ 9 ! mix+ *amb]1 :i* is simply a %ort l5g? ( pipe 7( ! same bore z ! eng9e induction pipe7 surr\nd$ by a hot-wat] jacket1 ! supply ( hot wat] be+ drawn f ! eng9e cool+ sy/em4 ,! heat f ?is jacket %\ld be suffici5t to make up = ! fall 9 temp]ature t w\ld o!rwise result due to ! vaporization ( ! petrol z expla9$ above4 ,illu/ration3 ,,fig4 #dj4--,,pla9 ,,=m ,,( ,,*oke ,,tube4 ,rec5t ,improvem5ts 9 ,c>burettors4--,ano!r defect ( ?is simple type ( c>burettor becomes app>5t 9 ! l>g] sizes requir$ = multi-cyl9d] eng9es4 ,to pass ! requisite quantity ( petrol to keep ! eng9e runn+ at high spe$s )\t creat+ too great a suction ef=t & !reby hamp]+ ! eng9e1 necessitates ! use ( a jet ( l>g] calibre1 s t ! liquid is no long] spray$ b issues 9 ! =m ( a f9e /ream :i* is n readily vaporiz$4 ,?is has be5 ov]come by ! use ( multiple-jet c>burettors :i* h sev]al jets ea* surr\nd$ by its own *oke tube1 b all controll$ by "o ?rottle valve & suppli$ f "o common float *amb]4 ,9 ?is case ! total cross-sectional area ( all ! jet orifices toge!r c\ld be made suffici5t to pass ! necess>y quantity ( fuel1 b ! bore ( ea* individual jet orifice w\ld be comp>atively small & spray+ w\ld result z be=e4 ,ano!r v successful device is %[n 9 ,fig4 #da1 9 :i* ,a is ! petrol jet :i*1 9 ?is case1 has no special orifice & is surr\nd$ by a l>g] tube ,b conta9+ small holes = ! inlet ( air & outfl[ ( petrol4 ,z ! petrol issues f ! jet x /rikes aga9/ ! po9t$ cone on ! end ( ! screw ,c1 & is ?us v successfully atomiz$ & brok5 into small p>ticles :i* c be readily vaporiz$4 ,illu/ration3 ,,fig4 #da4--,,petrol ,,jet1 ,,specially ,,arrang$ ,,= ,,atomis+ ,,! ,,petrol4 ,illu/ration3 ,,fig4 #db4--;,,comp5sat$ ,,petrol ,,jet4 ,a ,,is ,,! ,,ma9 ,,jet ,,& ,b ,,! ,,comp5sat+ ,,jet ,,suppli$ ,,?r\gh ,,! ,,orifice ,c4 ,!re are sev]al devices = keep+ ! /r5g? ( ! mixture con/ant at all eng9e spe$s irrespective ( ! am\nt ( vacuum 9 ! *oke tube4 ,"o ( ! be/ ( ^! is illu/rat$ 9 ,fig4 #db1 & consi/s 9 ! use ( a comp5sat+ jet4 ,! ma9 petrol jet ,a is ( suffici5t size to supply ! requirem5ts ( ! eng9e "u full spe$ & ) ! result+ high vacuum2 x is f$ directly f ! float *amb] 9 ! usual mann]4 ,! comp5sat+ jet ,b surr\nds ! ma9 jet & is suppli$ ) petrol ?r\gh an orifice ,c1 s arrang$ t x (f]s a great] resi/ance to fl[ ?an ! passage up ! c5tre ( ! ma9 jet4 ,at all eng9e spe$s up to a c]ta9 pr$et]m9$ maximum ! comp5sat+ jet w supply mo/ ( ! petrol1 b z ! dem& increases ! ma9 jet w also beg9 to supply1 & simultane\sly ! comp5sat+ jet w comm5ce to g out ( action ow+ to its supply ( petrol becom+ p>tly or :olly exhau/$ due to ! re/riction ( ! orifice ,c4 ,! simple jet-9-tube c>burettor has be5 greatly improv$ by ! addition ( an automatic extra-air valve1 ( :i* a simple =m is %[n 9 ,figs4 #dc & #dd4 ,x consi/s ( a small mu%room type valve ,a1 ) its seat+ ,b s arrang$ t x c be screw$ into ! induction pipe ( ! eng9e4 ,! valve is held up aga9/ its seat+ by a light spr+ ,c1 s t at high eng9e spe$s :5 !re is a good vacuum 9 ! induction pipe ! pressure ( ! atmosph]e w op5 ! valve aga9/ ! t5sion ( ! spr+ & all[ air to pass into ! induction pipe1 ?us r$uc+ ! am\nt ( vacuum & simultane\sly weak5+ ! mixture4 ,illu/ration3 ,,fig4 #dc4--;,,automatic ,,spr+ ,,controll$ ,,extra-,,air ,,valve4 ,illu/ration3 ,,fig4 #dd4--,,plan ,,view ,,( ,,automatic ,,extra-,,air ,,valve4 ,! po9ts ( a good c>burettor3-- ,^! may be set out 9 ! foll[+ ord]-- 7#a7 ,complete atomization & vaporization ( ! liquid fuel at all eng9e spe$s4 7#b7 ,! supply ( an adequate quantity ( gas ( ! correct proportions ) all ?rottle op5+s & at all temp]atures4 7#c7 ,suffici5t me*anical /r5g? & durability to )/& road %ocks & to ensure fre$om f breakd[ns )\t undue weight or complications4 7#d7 ,ability to cont9ue work+ correctly :5 ! c> is on an incl9e or affect$ by ! camb] ( ! highway4 7#e7 ,mod]ate fir/ co/4 ,pressure ,fe$ & ,gravity ,fe$4--,9 ,fig4 #ch we %[$ a gravity-f$ sy/em or "o 9 :i* ! petrol is f$ f ! tank to ! float *amb] ( ! c>burettor by ! action ( gravity only4 ,= ?is sy/em to be successful at all times ! c>burettor mu/ be plac$ l[ d[n to obta9 a good head = ! fl[ ( petrol 9 ! connect+ pipes1 z !re is a practical limit to ! height at :i* ! petrol tank c be fix$4 ,also ! pipes mu/ h a cont9u\s run d[n t[>ds ! float *amb] to prev5t air-locks 9 !m1 & !y mu/ be kept away f ! hot exhau/ sy/em4 ,:5 all ^! po9ts c be secur$ ?is sy/em is p]fect4 ,an alt]native sy/em is to =ce ! petrol into ! float *amb] by ma9ta9+ an air pressure 7( #b or #c lb4 p] squ>e in*7 on ! surface ( ! liquid 9 ! petrol tank4 ,) ?is arrangem5t ! c>burettor may1 if desir$1 be situat$ above ! level ( ! petrol tank 9 a m accessible position1 b x necessitates ! fitt+ ( a small air pump on ! eng9e & ! use ( a h& air pump = />t+4 ,,*apt] ,,vi ,,ignition ,,& ,,ignition ,,devices ,we h already /at$ t ! *>ge ( explosive mixture is ignit$ 9 ! cyl9d] at ! end ( ! compression /roke by means ( an electric sp>k4 ,! electric sp>k takes place z ! result ( an electric dis*>ge across ! gap betwe5 ! electrodes ( ! sp>k+ plug4 ,illu/ration3 ,,fig4 #de4--,,sectional ,,draw+ ,,( ,a ,,sp>k+ ,,plug4 ,! ,sp>k+ ,plug4--,two views ( a typical sp>k+ plug are %[n 9 ,figs4 #de & #df1 9 :i* ,a is ! high t5sion electrode :i* is p]iodically *>g$ ) electricity at high voltage 7or electrical pressure7 f a high t5sion magneto or a high t5sion coil1 & ,b#a1 ,b#b are electrodes :i*1 be+ 9 metallic contact ) ! cyl9d]s & framework ( ! eng9e1 are ?us at z]o pot5tial4 ,! electric dis*>ge occurs across ! gap ,c#a1 ,c#b 9 ! =m ( a sp>k or fla%4 ,! electrode ,a is heavily insulat$ f ! metal cas+ ,d ( ! sp>k+ plug by porcela9 insulators ,e & ,f4 ,! locknuts ,g & ,h s]ve to keep ! plug gas-tight & hold ! sev]al portions toge!r me*anically4 ,! t]m9al ,k is us$ = clamp+ ! wire 7or lead7 :i* br+s ! supply ( high t5sion electricity4 ,! high t5sion electric curr5t may be suppli$ ei!r by 7#a7 a magneto ma*9e or 7#b71 a coil & accumulator ignition sy/em4 ,illu/ration3 ,,fig4 #df4--;,a ,,sp>k+ ,,plug4 ,illu/ration3 ,,fig4 #dg4--,,outside ,,view ,,( ,a ,,high ,,t5sion ,,magneto4 ,illu/ration3 ,,fig4 #dh4--;,,end ,,view ,,( ,a ,,high ,,t5sion ,,magneto1 ,,%[+ ,,high ,,t5sion ,,di/ributor ,,& ,,l[ ,,t5sion ,,contact ,,break]4 ,! ,high ,t5sion ,magneto4--,9 ,figs4 #dg1 #dh & #di we %[ a mod]n high t5sion magneto suitable = a f\r-cyl9d] eng9e4 ,x consi/s ( ! /ation>y magnets ,a1 ! driv+ sp9dle ,b1 ! high t5sion electrode ,d1 ! high t5sion di/ributor ,c1 & ! l[ t5sion contact break] ,e4 ,! armature1 cond5s]1 & di/ributor ge> :eels are n %[n 9 ! draw+s1 b are situat$ inside ! ma*9e 9 ! space betwe5 ! high t5sion electrode ,d & ! l[ t5sion contact break] ,e4 ,z ! sp9dle ,b is rotat$ by ge>+ driv5 f ! eng9e crank%aft ! armature atta*$ to x g5]ates a high t5sion curr5t & a l[ t5sion curr5t4 ,! high t5sion curr5t passes to ! high t5sion electrode ,d & !nce across ! ma*9e to ! c>bon bru% ,h ( ! high t5sion di/ributor ,c4 ,! l[ t5sion curr5t passes ?r\gh ! plat9um-tipp$ contact screws ,f#a1 ,f#b ( ! l[ t5sion contact break]4 ,twice dur+ ea* revolution ( ! armature ^! contacts are sep>at$ ow+ to ! fibre block atta*$ to ! bell crank lev] ,g pass+ ov] ! /ation>y cams ,t#a1 ,t#b2 ?is con/itutes ! make-&-break device = int]rupt+ ! prim>y curr5t4 ,! mom5t>y int]ruption ( ! prim>y curr5t 9 ?is way causes a v great increase 9 ! electrical pressure 7or voltage7 ( ! second>y or high t5sion curr5t :i* is suffici5t to br+ ab\t ! sp>k dis*>ge across ! gap betwe5 ! electrodes ( ! sp>k+ plug4 ,s9ce !re are two ( ^! cams on ! l[ t5sion contact break] x w be und]/ood t ! armature c supply curr5t = two sp>ks 9 e revolution x makes4 ,if we be> ?is fact 9 m9d we w h no difficulty 9 det]m9+ ! relative spe$s ( ! magneto armature & ! eng9e crank%aft = any type ( eng9e4 ,a f\r-/roke eng9e requires "o sp>k 9 e two revolutions made by ! crank%aft1 s t a f\r-cyl9d] eng9e ( ?is type requires two sp>ks p] revolution1 & ! magneto armature mu/ run at crank%aft spe$4 ,a six-cyl9d] eng9e work+ on ! f\r-/roke cycle w\ld require ?ree sp>ks p] revolution1 b ! armature ( ! magneto only supplies two1 !re=e x mu/ be driv5 at "o-&-a-half times ! crank%aft spe$4 ,illu/ration3 ,,fig4 #di4--;,,end ,,view ,,( ,a ,,high ,,t5sion ,,magneto1 ,,%[+ ,,! ,,e>?+ ,,t]m9al 7,p74 ,! high t5sion di/ributor consi/s ( ! c>bon bru% ,h driv5 by ge>+ f ! magneto armature & ! metal segm5ts ,m#a1 ,m#b1 ,m#c1 ,m#d1 :i* are m\nt$ 9 a block ( insulat+ fibre4 ,!re mu/ be z _m segm5ts on ! di/ributor z !re are cyl9d]s on ! eng9e1 "o segm5t = ea* sp>k+ plug2 b ! armature _c supply m ?an two sp>ks p] revolution1 & !re=e if ! di/ributor has f\r segm5ts x mu/ be driv5 at half ! armature spe$1 & if x has six segm5ts x mu/ be driv5 at "o-?ird ( ! armature spe$4 ,ea* metal segm5t is electrically connect$ to a sp>k+ plug lead su* z ,l#a1 ,l#b1 ,l#c1 ,l#d4 ,! high t5sion electrode ,d is atta*$ to a light c>bon bru% :i* presses on a gunmetal collector r+ at ! high t5sion end ( ! armature w9d+4 ,a special t]m9al is provid$ at ,p1 s t :5 a wire is atta*$ to x & connect$ to ! frame ( ! eng9e 7usually ?r\gh a swit*7 ! l[ t5sion w9d+s are %ort-circuit$ or clos$ on !mselves1 & ! make-&-break has no effect1 because !re is always ! pa? ?r\gh ! swit* until x is op5$ aga94 ,"u ^! circum/ances ! voltage ( ! high t5sion circuit is n suffici5t to cause ! sp>k dis*>ge1 & ! ignition is !n said to be swit*$ (f4 ,! in/ant at :i* ! sp>k occurs may be advanc$ or made e>li] by mov+ ! rock] arm ,k1 :i* c>ries ! /ation>y cams ,t#a1 ,t#b backw>ds1 :]eas if x is mov$ =w>d ! ignition is ret>d$ & occurs lat] 9 ! /roke4 ,normal ignition occurs :5 ! lev] is midway 9 its range ( movem5t & corresponds to ! position ( ! pi/on :5 ! crank is on ! top dead-c5tre1 :]eas advanc$ ignition occurs j be=e ! pi/on has complet$ ! compression /roke1 & ret>d$ ignition w take place aft] ! crank has pass$ ! dead-c5tre & :5 ! pi/on has mov$ d[n a little on ! p[] 7or explosion7 /roke4 ,advanc+ ! ignition increases ! spe$1 & ret>d+ ! ignition r$uces ! spe$1 except :5 ! eng9e is ov]load$1 & !n x may pick up spe$ a little or run bett] if ! ignition is slightly ret>d$--b ! exact behavi\r w dep5d on ! temp]ature ( ! metal walls & pi/on )9 ! cyl9d]4 ,illu/ration3 ,,fig4 #ej4--;,,an ,,ignition ,,coil1 ,,%[+ ,,! ,,trembl] ,,me*anism4 ,we h m5tion$ t normal ignition occurs :5 ! crank is exactly on ! dead-c5tre & ! pi/on at ! top ( its /roke4 ,if we set ! magneto :5 ! eng9e is at re/ s t ignition ought to occur on dead-c5tre :5 ! arm ,k is 9 its mid position ! actual sp>k+ w be late on acc\nt ( ! "t lag ( ! electric curr5t4 ,! curr5t takes "t to fl[ & 9 t brief elem5t ( "t ! crank has mov$ a few degrees (f ! dead-c5tre1 at high spe$s4 ,h5ce ! ignition mu/ be advanc$ if ! *>ge is to be correctly fir$ :5 ! eng9e is runn+ fa/4 ,if ! ignition is too f> advanc$ x w cause ! eng9e to 8knock10 especially "u heavy loads4 ,if ! ignition is ret>d$ ! *>ge is n fir$ at ! comm5cem5t ( ! /roke s t a portion ( ! p[] !oretically available 9 ! fuel is lo/ to exhau/ at ! end ( ! /roke4 ,ret>d$ ignition always causes ov]heat+ ( ! exhau/ sy/em4 ,if ! arm ,k is fix$ me*anically 9 its mid position s t ! ignition c nei!r be advanc$ nor ret>d$1 we h :at is kn[n z fix$ ignition4 ,illu/ration3 ,,fig4 #ea4--;,,ignition ,,coil ,,case4 ,illu/ration3 ,,fig4 #eb4--,,l[ ,,t5sion ,,contact ,,break] ,,= ,,s+le ,,cyl9d] ,,coil ,,ignition ,,sy/em 7,,wipe ,,contact74 ,an ,ignition ,coil suitable = a s+le cyl9d] eng9e is %[n 9 ,figs4 #ej & #ea1 9 :i* ,a & ,b are ! l[ t5sion t]m9als & ,c is ! high t5sion t]m9al4 ,! trembl] blade is %[n at ,d1 ) ! adju/+ screw ,f & ! plat9um-tipp$ contacts ,g#a1 ,g#b4 ,! iron core ( ! coil projects a little above ! case1 z %[n at ,e 9 ,fig4 #ej4 ,! /r5g? & "* ( ! sp>k may be v>i$ consid]ably by slightly screw+ ,f up or d[n4 ,:5 curr5t is suppli$ to ! l[ t5sion t]m9als ( ! coil x fl[s ?r\gh ! prim>y w9d+ & magnetizes ! iron core1 complet+ its circuit by pass+ across ! plat9um contacts4 ,:5 ! trembl] blade is attract$ to ! iron core ! prim>y circuit is brok5 by ! tempor>y sep>ation ( ! plat9um contacts1 & !re=e ! magnetism ceases1 ! trembl] is releas$1 & ! circuit is complet$ aga94 ,?us ! trembl] blade is set rapidly vibrat+ & mak+ & break+ ! prim>y circuit z long z ! roll] atta*$ to ! rotat+ arm ,h ( ! l[ t5sion contact break] %[n 9 ,fig4 #eb is 9 contact ) ! metal segm5t ,k1 & ?is results 9 ! production ( a succession ( sp>ks at ! sp>k+ plug :i* is connect$ to ! t]m9al ,c ( ! high t5sion w9d+4 ,?is is v useful especially :5 />t+ an eng9e1 b ) mod]n high-spe$ eng9es ! trembl] has only "t to give "o sp>k at high eng9e spe$s1 & !re=e ! magneto has ! advantage except = easy />t+4 ,?is has l$ to ! introduction ( dual ignition sy/ems1 & 9 p>ticul> to t sy/em 9 :i* ! ma9 ignition is by magneto1 b !re is a supplem5t>y coil fitt$ to supply high t5sion curr5t to ! ord9>y high t5sion magneto di/ributor :5 ! eng9e is at re/1 ! coil be+ cut out aft] ! eng9e has got up spe$4 ,b ?is has be5 l>gely sup]s$$ by ! use ( electric motors = />t+ ! eng9e1 al?\gh ! magneto is /ill reli$ ^u = ! ignition ( ! *>ge 9 ! cyl9d]s4 ,! contact break] & coil j describ$ w\ld be v suitable = a s+le cyl9d] petrol eng9e1 or a non-trembl] coil might be us$ 9 conjunction ) a contact break] ( ! quick break type us$ on magnetos & illu/rat$ 9 ,fig4 #dh4 ,9 ! case ( a multi-cyl9d] eng9e hav+ coil ignition we may use sep>ate coils )\t a high t5sion di/ributor1 or a s+le coil & a high t5sion di/ributor hav+ z _m segm5ts z !re are eng9e cyl9d]s & arrang$ simil>ly to ! magneto di/ributor ( ,fig4 #dh4 ,:5 no high t5sion di/ributor is fitt$ !re mu/ be a sep>ate coil = ea* cyl9d]1 & ! high t5sion wire runs direct f ! coil to ! sp>k+ plug1 s t ! "* ( ! sp>k z well z ! exact in/ant at :i* x occurs may n be ! same 9 ea* ( ! cyl9d]s4 ,if !re is a high t5sion di/ributor x %\ld be m\nt$ on ! same driv+ sp9dle z ! l[ t5sion contact break]1 9 ord] t ! ignition may be syn*roniz$1 i4e41 ! sp>k w occur at ! same po9t 9 ! pi/on's /roke = all ! cyl9d]s4 ,! ignition may be advanc$ or ret>d$ by mov+ ! cas+ ( ! l[ t5sion contact break] relative to ! roll] arm1 ?us caus+ x to make contact ei!r e>li] or lat] 9 ! revolution4 ,at "o "t x 0 ?\ght t two-po9t ignition gave increas$ p[] & effici5cy4 ,two-po9t ignition means simultane\s fir+ ( ! *>ge f m ?an "o plug4 ,sometimes two high t5sion leads 7 l$ f ea* di/ributor segm5t & connect$ to ! two plugs 9 ! correspond+ cyl9d]--?is con/itut$ ! p>allel sy/em4 ,ano!r sy/em employ$ a special plug ) bo? electrodes insulat$ f ! eng9e frame2 ?is 0 c\pl$ 9 s]ies ) an ord9>y plug s t ! sp>k jump$ ! gaps 9 succession4 ,x is q evid5t1 h[ev]1 t if ! gas is ?or\ghly mix$ up & 9 a /ate ( viol5t agitation z ! result ( rapid compression1 a s+le well-plac$ sp>k w fire x successfully & s no ga9 results f simultane\s ignition at ano!r & less fav\r$ po9t4 ,illu/ration3 ,,fig4 #ec4--,,wir+ ,,diagram ,,= ,,f\r ,,cyl9d] ,,eng9e ,,) ,,high ,,t5sion ,,magneto ,,ignition4 ,wir+ ,diagram = ,magneto ,ignition ,sy/em4--,! electrical connexions are extremely simple 9 ! case ( a high t5sion magneto ignition sy/em4 ,9 ,fig4 #ec we %[ a f\r-cyl9d] eng9e fitt$ ) high t5sion magneto4 ,! only wires requir$ are ! f\r high t5sion cables f ! high t5sion di/ributor to ! sp>k+ plugs & ! e>?+ wire lead+ f ! %ort circuit+ t]m9al to ! frame ( ! eng9e ?r\gh a swit* z indicat$4 ,! fir+ ord] ( ! cyl9d]s may be ei!r #a1 #c1 #d1 #b or #a1 #b1 #d1 #c1 z desir$ 7provid$ ! cranks are arrang$ 9 ! usual mann]1 t is1 9 ! ord] %[n 9 ,fig4 #ba74 ,9 det]m9+ ! ord] ( fir+ ( ! respective cyl9d]s ! eng9e %\ld be turn$ r\nd v sl[ly by h& & c>eful note made ( ! ord] 9 :i* ! fir+ /rokes occur4 ,to det]m9e ! fir+ /roke ! pi/on %\ld be mov+ d[nw>ds & ! position ( ! valves not$2 if bo? valves are %ut !n ?is is ! fir+ /roke1 b if ! inlet valve is op5+ x is ! suction /roke4 ,wir+ ,diagram = a ,coil ,ignition ,sy/em4--,! electrical connexions = a coil ignition sy/em are slightly m difficult to foll[ out2 !y are %[n 9 ,fig4 #ed = ! same eng9e illu/rat$ 9 ,fig4 #ec4 ,9 ! diagram we %[ f\r sep>ate trembl] patt]n coils1 ea* ( :i* c give a succession ( sp>ks z long z contact is be+ made on any "o segm5t ( ! l[ t5sion contact break] connect$ to x4 ,all ! l[ t5sion t]m9als ( ! coils are connect$ toge!r to a common busb>1 :i* is suppli$ ) curr5t f ! accumulator direct4 ,! curr5t fl[s f ! busb> ?r\gh ! l[ t5sion w9d+s ( ea* ( ! coils 9 turn1 z x comes into op]ation ?r\gh ! eng9e-driv5 contact break]1 & returns to ! batt]y ?r\gh ! frame ( ! eng9e4 ,high t5sion cables lead f ! high t5sion t]m9al ( ea* coil direct to ! sp>k+ plugs1 & !re=e ! ignition is n necess>ily syn*roniz$4 ,illu/ration3 ,,fig4 #ed4--,,wir+ ,,diagram ,,= ,,f\r ,,cyl9d] ,,eng9e ,,) ,,trembl] ,,coil ,,ignition4 ,:5 ! swit* 9 ! l[ t5sion circuit is op5$ ! ignition is (f1 because ! curr5t is !n p]man5tly int]rupt$2 :5 ! swit* is clos$ ! ignition is on4 ,to economize curr5t a quick make-&-break device %\ld be us$ in/ead ( ! wipe =m ( contact break] illu/rat$1 & a non-trembl] coil us$4 ,x is v important to fully ret>d ! ignition lev] :5 />t+ an eng9e hav+ coil ignition1 because x is v liable to backfire & injure ! op]ator's wri/2 ) magneto ignition ?is is less liable to happ54 ,tim+ ! ,ignition4--,v>i\s in/ructions are giv5 f "t to "t = correctly tim+ magneto ignition1 b ! foll[+ w be f\nd to give satisfactory results4 ,fir/ asc]ta9 ! fir+ ord] ( ! cyl9d]s z expla9$ above1 & !n br+ ,no4 #a pi/on on to ! top dead-c5tre4 ,rotate ! driv+ sp9dle ( ! magneto until ! c>bon bru% ,h ( ! high t5sion di/ributor makes contact on ! segm5t connect$ to ! lead m>k$ 7#a74 ,if ! leads are n m>k$ x w be necess>y to det]m9e :i* is ,no4 #a by obs]v+ ! direction ( rotation ( ! bru%4 ,next adju/ ! position ( ! driv+ sp9dle v c>efully by turn+ x to & fro1 s t :5 ! ignition lev] ,k 7see ,fig4 #dh7 is 9 its mid position ! plat9um contacts ,fl1 ,f#b are fully sep>at$1 ! bru% ,h /ill be+ on segm5t ,no4 #a4 ,!n pu% ! magneto ge> :eel into me% ) ! eng9e ge> :eel :i* is to drive x1 & firmly bolt d[n ! magneto to its bracket4 ,simil> in/ructions may be foll[$ out = ! coil ignition sy/em4 ,,*apt] ,,vii ,,lubrication ,prop]ties ( ,oils4--,ow+ to ! v high spe$ at :i* ! mod]n petrol eng9e runs great att5tion mu/ be paid to lubricat+ ! mov+ p>ts1 o!rwise undue we> or ev5 seizure w result4 ,we mu/ be v c>eful to *oose a suitable oil1 "o :i* is *emically pure & reta9s its lubricat+ prop]ties at high temp]atures4 ,a consid]able am\nt ( oil f9ds its way into ! cyl9d]1 :]e x comes into direct contact ) ! hot gases4 ,if an oil is heat$ a temp]ature w soon] or lat] be atta9$1 :5 ! oil w give (f an inflammable vap\r1 i4e41 "o :i* w burn4 ,?is temp]ature is call$ ! fla% po9t ( ! oil4 ,if ! oil is likely to get into ! cyl9d] ( a petrol eng9e x %\ld h a v high fla% po9t2 9 fact1 mo/ ( ^! oils d n fla% until well ov] #djj ,fahr5heit4 ,also :5 ! oil is burnt x mu/ n leave any appreciable residue4 ,"s oils are v defective 9 ?is respect1 & leave l>ge quantities ( c>bon deposit on ! metal walls ( ! cyl9d] & ! valves2 o!rs aga9 are gummy or too visc\s ev5 at high temp]atures4 ,su* oils mu/ be avoid$ equally ) ^? :i* lose _! viscosity too mu* "u heat4 ,spla% ,sy/em ( ,lubrication4--,"o me?od ( lubricat+ ! work+ p>ts is kn[n z ! spla% sy/em4 ,9 ?is sy/em oil is p\r$ into ! crank*amb] & ! mov+ p>ts dip into x1 spla%+ x all ov] ! int]ior ( ! crankcase & ! l[] portions ( ! cyl9d] walls4 ,oil holes are drill$ 9 su* positions t z ! oil drops d[n aga9 aft] be+ spla%$ upw>ds "s ( x w fall into ^! holes & lubricate ! be>+s4 ,?is is a v *eap me?od ( lubrication 9 fir/ co/1 b v wa/eful & unsatisfactory 9 regul> use1 h5ce x has practically di$ out4 ,z ! oil is us$ up a fre% supply mu/ be admitt$ by "s =m ( cont9u\s drip-fe$ arrangem5t1 ! oil be+ =c$ ov] v (t5 f a small tank on ! footbo>d by means ( air pressure or ! pressure ( ! exhau/ gases f ! eng9e4 ,x is v difficult "u ^! circum/ances to e/imate h[ mu* oil is pres5t 9 ! crank*amb] at any giv5 in/ant1 s t !re 0 usually alt]nately too mu* or too little4 ,too little oil meant undue we> on be>+s 7p]haps seizure71 & too mu* oil meant a smoky exhau/ :i* became v obnoxi\s :5 ! eng9e 0 sudd5ly accel]at$4 ,illu/ration3 ,,fig4 #ee4--;,,improv$ ,,sy/em ,,( ,,spla% ,,lubrication4 ,improv$ ,sy/em ( ,spla% ,lubrication4--,?is is a comb9ation ( ! spla% sy/em & ! =c$ sy/em1 & is %[n 9 ,figs4 #ee & #ef4 ,9 ^! figures ,a#b & ,a#c repres5t two ( ! ma9 eng9e be>+s :i* support ! crank%aft2 ,c#a1 ,c#b1 ,c#c are ?ree ( ! crankp9s2 ,f#a1 ,f#b1 ,f#c are oil tr\ghs plac$ "u ! crankp9s2 ,d#b1 ,d#c are oil fe$ pipes to ! ma9 be>+s4 ,g5]ally speak+1 ! oil is drawn f ! bottom ( ! crankcase by means ( a pump1 & ?is pump deliv]s ! oil to "s =m ( indicator m\nt$ on ! da%bo>d ( ! c>4 ,aft] pass+ ?r\gh ! indicator ! oil fl[s by two ma9 pipes1 "o ( :i* fe$s ! ma9 be>+s by means ( bran*es ,d#b1 ,d#c1 etc41 & ! o!r fe$s oil tr\ghs by means ( bran*es su* z ,g#b4 ,:5 ! tr\ghs are full ! oil ov]fl[s into ! bottom ( ! crank*amb]1 & s !re is always a con/ant dep? ( oil = ! scoops atta*$ to ! connect+ rod ends to dip into1 & "o great drawback to ! spla% sy/em is ov]come2 also ! ma9 be>+s are always sure ( be+ amply suppli$4 ,! oil pump may be an ord9>y plung] type pump or a rot>y pump4 ,illu/ration3 ,,fig4 #ef4--,,sectional ,,view ,,( ,,end ,,( ,,connect+ ,,rod1 ,,%[+ ,,arrangem5t ,,( ,,scoop ,,& ,,oil ,,tr\gh4 ,=c$ ,lubrication4--,"o sy/em ( =c$ lubrication is %[n 9 ,fig4 #eg4 ,! g5]al arrangem5t ( ! sy/em is v simil> to ! prec$+ "o1 except t !re are no tr\ghs 9 ! crank*amb] & all ! be>+s receive an ample supply ( oil "u pressure s t ! j\rnals are support$ 9 _! be>+s on a film ( oil & ! metals nev] come 9 direct contact ) ea* o!r4 ,aft] ent]+ ! ma9 be>+s ! oil passes ?r\gh holes drill$ 9 ! crank%aft & ?us positively lubricates ! crankp9 be>+1 pass+ up ! connect+ rod ei!r int]nally z %[n or by an ext]nal pipe x lubricates ! gudgeon p9 & !n falls d[n into ! crank*amb]4 ,on its way d[n x gets spla%$ ab\t & ?us lubricates ! cyl9d] walls & pi/on2 sometimes ^! are positively lubricat$ by lead+ ! oil ?r\gh ! c5tre ( ! gudgeon p9 direct to ! surface ( ! cyl9d] walls--b ?is (t5 gives an excess ( oil & causes a smoky exhau/4 ,9 ,figs4 #eh & #ei we %[ two views ( a v popul> =m ( oil pump = =c$ lubrication sy/ems4 ,x consi/s ( two ge> :eels1 "o ( :i* is driv5 by a sp9dle f ! eng9e crank%aft1 & x drives ! second :eel by means ( ! project+ tee?4 ,! oil is pick$ up by ! tee? & pass$ r\nd f ! suction to ! deliv]y side ( ! pump on ! out] edge ( ! :eels2 no liquid c pass direct across betwe5 ! tee? :i* are 9 me%1 & h5ce ! direction ( rotation is z %[n by ! arr[s4 ,illu/ration3 ,,fig4 #eg4--;,,=c$ ,,lubrication ,,sy/em4 ,illu/ration3 ,,fig4 #eh4 ,illu/ration3 ,,fig4 #ei4 ,,two ,,views ,,( ,a ,,rot>y ,,oil ,,pump ,,= ,,=c$ ,,lubrication4 ,! difficulty ( secur+ a really good lubricant = petrol eng9es mu/ be app>5t f a /udy ( ! prices ( ! v>i\s oils4 ,x w be obs]v$ t !y are all consid]ably m exp5sive ?an petrol1 & !re=e we mu/ economize 9 _! use4 ,! old spla% sy/em 0 v wa/eful & consum$ oil at ! rate ( "o gallon e hundr$ miles at lea/1 b a mod]n sy/em ( =c$ lubrication w n require m ?an "o gallon ( oil e ?\s& miles4 ,p]haps an av]age ev]yday figure = ord9>y motor-c> eng9es w\ld be "o gallon e #bej miles4 ,! pressure ( ! oil 9 a =c$ fe$ sy/em v>ies 9 diff]5t makes ( eng9es f #e up to #dj p\nds p] squ>e in*--a v common figure1 h[ev]1 is #aj p\nds p] squ>e in*4 ,! spe$ ( ! oil pump also v>ies consid]ably1 & ranges f #ejj up to #b1jjj revolutions p] m9ute at normal eng9e spe$4 ,g5]ally a small relief valve is fitt$ 9 ! pump cas+1 :i* returns oil to ! crank*amb] if ! pressure t5ds to rise above ! desir$ limit due to ! eng9e spe$ increas+4 ,we h m5tion$ already t ! fla% po9t is g5]ally ov] #djj ,fahr5heit :5 ! oil is new1 b aft] x has be5 9 ! crankcase "s "t & got us$ ov] & ov] aga9 x is f\nd t ! petrol vap\r leak+ pa/ ! pi/on r+s ( ! eng9e cond5ses :5 ! eng9e cools d[n aft] a run & drops into ! oil 9 ! sump1 ?us l[]+ its viscosity & its fla% po9t4 ,accord+ to ,mr4 ,morcom x may come d[n z l[ z #bjj ,fahr5heit 7ab\t71 b if ! oil is heat$ & ! petrol driv5 (f ! fla% po9t goes up aga94 ,!re=e x is a good plan ) =c$ lubrication sy/ems to empty ! old oil out p]iodically & fill up entirely ) fre% oil4 ,,*apt] ,,viii ,,cool+ ,we h already expla9$ ! necessity = cool+ ! cyl9d]s ( a petrol eng9e by means ( a wat]-jacket1 & we n[ proce$ to %[ h[ ! circulation sy/em may be arrang$4 ,!re are two =ms ( circulation 9 use3 7#a7 ,natural2 7#b7 ,=c$4 ,illu/ration3 ,,fig4 #fj4--,,!rmo-,,syphon ,,wat] ,,cool+ ,,sy/em4 ,natural or ,!rmo-,syphon ,circulation4--,?is sy/em is %[n 9 ,fig4 #fj1 & may be expla9$ z foll[s3--,! heat g5]at$ by ! successive explosions )9 ! cyl9d] causes ! wat] at ! top ( ! cyl9d] jacket ,a to get hot4 ,z a column ( hot wat] is light] ?an "o ( cold wat] ( equal height1 ! heat$ wat] rises up ! pipe ,b & fl[s into ! top ( ! radiator ,d1 :ile cold] wat] f ! bottom ( ! radiator fl[s up ! pipe ,c & into ! cyl9d] jacket ,a4 ,x is important t ! height ( ! wat] 9 ! radiator ,d %\ld be at su* a level t ! outlet f ! pipe ,b is subm]g$4 ,illu/ration3 ,,fig4 #fa4--;,,=c$ ,,wat] ,,circulation ,,by ,,means ,,( ,a ,,pump 7,p74 ,9 ! radiator ! wat] falls ?r\gh a s]ies ( tubes ,e1 hav+ gills or f9s on ! outside = ! purpose ( dissipat+ ! heat4 ,! cool+ ( ! wat] is also assi/$ by ! fan ,f1 :i* is driv5 f ! fan pulley ,g & draws air pa/ ! radiator tubes at high spe$4 ,sometimes ! wat] 9 ! radiator is made to fall ?r\gh a s]ies ( cells :i* are =m$ ( ca/ alum9ium2 su* a radiator is call$ a honeycomb radiator4 ,x is important t ! pipe ,c %\ld n h any %>p b5ds & x %\ld n rise v mu* 9 height1 b ! outlet pipe ,b may h a consid]able rise ) advantage4 ,bo? ! inlet & outlet pipes %\ld be ( l>ge diamet] ) ?is sy/em ( circulation1 & ! radiator %\ld be s arrang$ t !re is a good head ( wat] above ! cyl9d]s4 ,9 ! draw+s ,h is ! front cross-memb] ( ! *assis1 ,k is ! />t+-h&le clut*1 & ,l is ! />t+ h&le4 ,=c$ or ,pump ,circulation4--,) ?is sy/em ! wat] is positively circulat$ ?r\gh ! jackets2 x is drawn f ! bottom ( ! radiator by ! pump ,p 7,fig4 #fa71 :i* is me*anically driv5 f ! valve %aft ( ! eng9e1 & deliv]$ "u pressure to ! jacket ,a4 ,! outlet ( ! pipe ,b ne$ n be dr[n$1 & ! pipe ,c may be arrang$ 9 any way mo/ conv5i5t to ! *assis4 ,sometimes :5 a pump is fitt$ ! pipes are arrang$ s t ! sy/em may be op]at$ z a !rmo-syphon 9 ! ev5t ( a breakd[n ( ! pump4 ,x is n uncommon to exp]i5ce tr\ble due to leakage at ! pump gl&1 :i* results 9 gradual loss ( wat] f ! sy/em1 & !re=e ! !rmo-syphon or natural circulation has mu* to recomm5d x4 ,also x may be said t ! pump repres5ts an additional complication to ! eng9e & means increas$ fir/ co/4 ,e mov+ "p we add to ! eng9e is ( c\rse an additional pot5tial s\rce ( tr\ble1 b ! addition ( a really fir/-class wat] circulat+ pump ( ! type %[n 9 ,fig4 #eh _c be said to be any?+ b a reasonable precaution4 ,! weight & size ( e "p ( a motor-c> eng9e & *assis h be5 s mu* r$uc$ rec5tly1 ow+ to competition ) ,am]ican firms1 t _m manufactur]s :o adopt$ ! !rmo-syphon pr9ciple exp]i5c$ great tr\ble ) x ow+ to ! small size ( radiator fitt$1 z well z faulty arrangem5t ( ! connexions4 ,consid]+ any "o eng9e1 x foll[s t if a c]ta9 size ( radiator & a giv5 quantity ( wat] 9 ! circulat+ sy/em w keep ! eng9e cool :5 a pump is us$ to give a positive circulation1 !n a l>g] radiator & great] quantity ( wat] w be requir$ = natural circulation4 ,!rmo-syphon circulation also means a high radiator & bonnet1 :i* _m p object to on ! score ( appe>ance1 )\t consid]+ its utility4 ,) natural circulation great] c>e mu/ be ex]cis$ to keep ! radiator well fill$1 b ?is (t5 leads to o!r difficulties on bad roads ow+ to ! wat] spla%+ f ! ov]fl[ pipe & f9d+ its way on to ignition appliances4 ,be=e />t+ an eng9e x is always advisable to remove ! radiator fill+ cap & exam9e ! wat] level2 if x %\ld happ5 t at any "t :ile ! eng9e is runn+ ! circulat+ sy/em runs q dry1 ow+ to a breakd[n or leakage1 d n attempt to p\r wat] into ! radiator1 b simply raise bo? sides ( ! bonnet & leave ! eng9e to cool d[n fir/4 ,aga91 :5 fill+ ! radiator = a =c$ circulat+ sy/em1 x is desirable to give ! eng9e a turn or two ) ! />t+ h&le occasionally to op]ate ! pump & prev5t air locks2 v (t5 ! radiator appe>s to be full1 b z soon z ! eng9e comm5ces to run ! wat] disappe>s ow+ to ! sy/em n be+ full1 due to ! above-m5tion$ cause4 ,9 cold or fro/y wea!r all ! wat] %\ld be dra9$ (f f ! circulat+ sy/em :5 ! c> is 9 ! g>age1 unless ! g>age is heat$ or "s anti-freez+ solution is us$4 ,glyc]9e or alcohol add$ to ! wat] w prev5t x freez+1 b z an additional precaution 9 cold c\ntries "o (t5 sees travell+ rugs /rapp$ ov] ! radiator & bonnet4 ,occasionally "o gets tr\ble due to ! wat] boil+ 9 ! jackets1 & on ?is acc\nt reasonable c>e %\ld always be ex]cis$ 9 unscrew+ ! radiator fill+ cap if ! pres5ce ( /eam is suspect$4 ,an eng9e may h be5 runn+ well = a long "t )\t tr\ble & !n develop symptoms ( ov]heat+ 9 ! circulation sy/em4 ,?is ov]heat+ may be ei!r local or g5]al4 ,local ov]heat+ may result f "s p>tial seizure ( ! pi/on 9 ! cyl9d] due to dirt on ! walls1 or f ! pres5ce ( grease on ! outside ( ! cyl9d] walls1 9 ! jacket space4 ,if grease is suspect$ or !re is furr+ up 9 ! passages ( ! jacket due to bad wat] supply1 ! tr\ble may be cur$ by add+ "s common wa%+ soda to ! wat] 9 ! radiator & runn+ ! eng9e ) ! c> at /&/ill = half-an-h\r or s4 ,aft] ?is dra9 (f all ! wat] & sludge1 all[ ! eng9e to cool d[n1 & !n fill up aga9 ) clean wat]4 ,g5]al ov]heat+ may result f leaky pi/ons & pi/ons r+s1 or f ! use ( too weak a mixture 9 ! c>burettor1 or f ov]load+ ! eng9e4 ,if ! mixture suppli$ to ! eng9e is v weak1 ! ov]heat+ w be v m>k$ on ! exhau/ side ( ! eng9e4 ,local ov]heat+ causes ! eng9e to 8knock0 badly4 ,9 arrang+ ! jackets & ! pipes c>e mu/ be tak5 to arrange t a cock is plac$ at ! l[e/ po9t 9 ! sy/em1 s t ! :ole may be completely empti$1 & ! inlet pipe to ! jacket %\ld ent] at ! v bottom ( ! jacket *amb] = ! same reason4 ,x may be ?\ght t all t is necess>y is to provide pl5ty ( space 9 ! jackets r\nd ! cyl9d]s & pl5ty ( wat] 9 ! :ole sy/em1 b exp]i5ce %[s t x is v important n to make ! jacket space too l>ge1 s z to ensure positive circulation & avoid local circulation 9 any "o portion ( ! jacket4 ,:5 cyl9d]s are ca/ 9 pairs ! back pair h a t5d5cy to dis*>ge _! hot wat] into ! front pair & s back to ! inlet pipe aga91 h5ce ?is %\ld be gu>d$ aga9/ 9 arrang+ ! outlet pipes4 ,pipes suitable = use ) multi-cyl9d] eng9es are %[n 9 ,fig4 #fb1 9 :i* 7a7 is an outlet pipe = a monobloc ca/+1 & 7b7 & 7c7 are inlet & outlet pipes respectively = eng9es hav+ sep>ate cyl9d]s4 ,x is advisable to modify ! diamet] ( ! bran*es by ! ins]tion ( metal orifice plates at ! flanges to ensure an equitable di/ribution ( ! wat] among ! sev]al cyl9d]s4 ,illu/ration3 ,,fig4 #fb4--;,,=ms ,,( ,,wat] ,,pip+4 ,! weight ( wat] c>ri$ 9 ! circulation sy/em = a fifte5 horse-p[] eng9e w\ld be ab\t #cj lb4 ) pump circulation1 :]eas #fj lb4 w\ld be requir$ = !rmo-syphon cool+4 ,x is n desirable to cool ! eng9e too mu*4 ,! jacket wat] temp]ature may be all[$ to rea* #ahj ,fahr5heit at full load1 b if ?is is exce$$ !re is liability to boil+4 ,giv5 two simil> eng9es ( equal p[] & equally load$1 "o ( :i* 0 op]at$ ) a jacket temp]ature ( #ajj ,fahr5heit & ! o!r at #ahj ,fahr5heit1 ! hott] eng9e w\ld %[ a ga9 9 economy ( f five to t5 p] c5t4 9 fuel consumption4 ,9 consid]+ ! type ( radiator to adopt1 "o w\ld n recomm5d ! honeycomb v>iety 7except = appe>ance7 ow+ to ! difficulty ( clean+ ! passages aft] x has be5 9 use "s "t2 & ! gill$ tube w\ld be m effici5t ?an ! pla9 tube4 ,! am\nt ( tube requir$ dep5ds ( c\rse on its diamet]1 b a r\gh approximation w\ld be twelve feet ( gill$ tube or eighte5 feet ( pla9 tube 7( half-in* diamet]7 p] brake horse-p[]4 ,,*apt] ,,ix ,,! ,,po9ts ,,( ,a ,,good ,,eng9e ,*oos+ ! ,numb] ( ,cyl9d]s4--,x is a v difficult problem to select ! be/ eng9e = a p>ticul> purpose1 z !re are s _m factors :i* influ5ce "o's *oice4 ,a s+le cyl9d] eng9e w\ld only be us$ = a motor-cycle or a small c> ( l[ p[]2 ! vibration & noise result+ f ! use ( a s+le cyl9d] petrol eng9e ( ev5 six horse-p[] are mo/ objectionable1 & difficulties ( />t+ & risk ( eng9e unexpect$ly pull+ up & /opp+ are greatly enhanc$4 ,! two-cyl9d] eng9e (f]s bett] prospects1 & 0 = "s "t consid]$ q good en\gh = mo/ purposes1 b ow+ to its comp>atively bad balance & its l[ torque x has fall5 into disfav\r4 ,we h se5 h[ ! rotat+ p>ts ( ! eng9e c be balanc$1 b we h n consid]$ ! reciprocat+ p>ts4 ,to und]/& ?is "q ( balanc+ we mu/ talk ab\t 8in]tia =ces40 ,all bodies possess in]tia1 t is1 !y res5t *anges 9 _! /ate ( re/ or motion4 ,if a body is mov+ uni=mly x t5ds to keep on do+ s1 :]eas if x is at re/ x t5ds to rema9 s4 ,to />t ! body (f f re/1 or to /op ! body & br+ x to re/1 requires a =ce to be ex]t$1 & ?is =ce may be call$ ! in]tia =ce4 ,:5 a petrol eng9e is runn+ at high spe$ ! pi/on has to be />t$ & /opp$ at ! top & bottom ( its /roke e "t ! crank%aft revolves once1 & to d ?is v l>ge =ces are ne$$1 because x has to be done s quickly4 ,^! in]tia =ces take ! =m ( pu%es or pulls on ! %aft & framework ( ! eng9e1 & ?us cause vibrations to be set up4 ,if ! p]iodicity or frequ5cy ( ^! =c$ vibrations happ5s to co9cide ) ! natural p]iod ( vibration ( ! %aft mat]ial ! %aft w comm5ce to :ip1 & may possibly break "u ! excessive /ra94 ,9 a two-cyl9d] eng9e ) cranks #ahj degrees ap>t 7or half a revolution7 "o pi/on is mov+ upw>ds & ! o!r pi/on is mov+ d[nw>ds1 bo? at v high spe$2 & bo? h to be br\ght to re/ :5 ! cranks come on _! respective dead-c5tres4 ,! pi/on :i* is mov+ up t5ds to lift ! %aft up ) x1 & ! "o :i* is mov+ d[n t5ds to pull ! %aft d[n ) x1 because ! connect+ rods *eck ! progress ( ! pi/ons & br+ !m to re/ at ! top & bottom ( _! /rokes4 ,if ^! two pulls act$ 9 l9e ) ea* o!r !y w\ld balance1 b ! cyl9d]s are usually m\nt$ side by side1 & !n ! two pulls virtually act at ! ends ( a b> ^: l5g? is ! longitud9al di/ance betwe5 ! v]tical c5tre l9es ( ! two cyl9d]s4 ,?us ^! two in]tia =ces t5d to rotate ! :ole eng9e fir/ 9 a clockwise direction & !n 9 a c\nt]-clockwise direction1 accord+ to :i* pi/on is mov+ up or d[n4 ,! only way to balance ^! =ces "u ^! conditions is to ext5d ! crank%aft longitud9ally & place ano!r pair ( cyl9d]s & cranks 9 l9e ) ! fir/1 b s arrang$ t ! in]tia =ces t5d to turn ! eng9e 9 ! opposite direction to ! fir/ pair4 ,?is gives u ! well kn[n f\r-cyl9d] arrangem5t s mu* 9 evid5ce at ! pres5t "t1 ! arrangem5t ( cranks be+ %[n 9 ,fig4 #ba4 ,a six-cyl9d] eng9e gives p]fect balance if all ! p>ts are ( equal weight1 & ! cranks at #abj degrees to ea* o!r 9 oppos$ pairs4 ,aga91 a s+le-cyl9d] eng9e gives "o p[] /roke 9 e two revolutions ( ! %aft1 a two-cyl9d] gives a p[] /roke 9 e revolution1 a f\r-cyl9d] gives two p[] /rokes1 & a six-cyl9d] gives ?ree p[] /rokes 9 e revolution ( ! %aft4 ,h5ce a six-cyl9d] eng9e is v flexible 7i4e41 c accommodate itself easily to v>y+ loads71 is p]fectly balanc$1 & c be made bo? p[]ful & economical4 ,"o objection to ! use ( eng9es ) multiple cyl9d]s 7exce$+1 say1 f\r 9 numb]7 is t ! crank%aft is m liable to vibrate & cause v h>% runn+ at high spe$s on acc\nt ( ! fact t ! p]iodicity ( ! p[] impulses imp>t$ to ! %aft approa*es ! natural p]iod ( vibration ( ! %aft4 ,?is effect arises f torsional oscillations & is di/9ct f ! p]iodicity due to in]tia =ces :i* acts 9 ! v]tical plane4 ,a f\r-cyl9d] eng9e is ne>ly z good z a six-cyl9d] ( equal p[]1 & is ( c\rse mu* *eap] 9 fir/ co/1 takes up less room1 & weighs less4 ,a good f\r-cyl9d] eng9e w (t5 prove m economical 9 runn+ co/s ?an a six-cyl9d]1 z x w probably be runn+ a great] l5g? ( "t at or ne> its full output1 & ! "w done on ! idle /rokes ( ! cycle w be less ow+ to ! small] numb] ( cyl9d]s4 ,ano!r feature to consid] is ! arrangem5t ( ! cyl9d] ca/+s4 ,a monobloc ca/+ 7cyl9d]s all 9 "o ca/+7 gives a v %ort eng9e & r$uces ! l5g? ( ! crank%aft1 b 9 ! ev5t ( "o cyl9d] bore be+ damag$ ! advantage lies ) ! sep>ate cyl9d] con/ruction4 ,! ,"q ( ! ,valves4--,! "q z to :i* is ! bett] eng9e1 ! sleeve valve or ! poppet valve1 _c be said to h be5 def9itely decid$ yet4 ,! great feature ( ! poppet valve us$ to be its v quick op5+ & clos+1 b n[adays eng9es turn ov] s fa/ t v /rong spr+s are ne$$ to close ! valves 9 a reasonable "t4 ,"o complete revolution ( ! eng9e means t ! crank has turn$ ?r\gh #cfj degrees1 & ! inlet valve is op5 :ile ! crank turns ?r\gh #aij degrees 7on ! av]age71 b dur+ "p ( ?is "t x is be+ lift$ or op5$1 & dur+ an equal p]iod x is be+ clos$4 ,! "q !n is1 8,h[ long does x rema9 fully op580 ,! answ] is--n m ?an t5 degrees at ! mo/6 ,to keep ! inlet valve op5 long] ?an ?is w\ld require excessively /iff spr+s & ?r[ a great /ra9 on ! valve ge>4 ,n[ ?is is :]e ! sleeve valve manag$ to get a look 9--z "o might say4 ,) two sleeves mov+ 9 opposite directions1 or "o sleeve receiv+ a special =m ( motion1 we c op5 & close ! ports & keep !m fully op5 = j z long p]iod or ev5 long] ?an ! poppet valve4 ,if x 7 n = ! fact t sleeve valves are heavy & n s easy to keep gas-tight z poppet valves1 x is p]fectly obvi\s t ! poppet valve w\ld h disappe>$ or tak5 second place long be=e ?is4 ,ano!r great advantage ( ! sleeve valve is t by mak+ l>ge ports we c easily secure l>g] valve op5+s ?an are possible1 = practical reasons1 ) a poppet valve4 ,x is n[ claim$ also t ! int]ior ( ! cyl9d]s keeps free f c>bon deposit mu* long] ) sleeve valves ?an ) poppet valves1 ?is c>bon deposit be+ due *iefly to ! use ( too ri* a mixture :i* causes ! combu/ion to be imp]fect & results 9 ! deposit ( solid c>bon on ! walls & sides ( ! combu/ion *amb]4 ,c>bon deposit is also caus$ by us+ unsuitable lubricat+ oil1 b x pr9cipally arises f ! use ( too ri* a mixture = ! purposes ( secur+ quick accel]ation4 ,p]fect combu/ion is only secur$ by ! use ( a relatively weak mixture1 :i* w\ld prev5t ! maximum p[] be+ develop$ & give r a feeble accel]ation4 ,mod]n eng9es h to be v c>efully design$ to r$uce ?is nuisance ( ! c>bon deposit to a m9imum1 & also ) a view to its spe$y & effici5t removal :5 x does take place4 ,deta*able cyl9d] heads h be5 introduc$ pr9cipally to all[ ( rapid removal ( c>bon deposit f pi/ons & valves & ! combu/ion *amb]4 ,if ! c>bon deposit is all[$ to accumulate1 p9k+ or %>p knock+ comm5ces1 due to pre-ignition ( ! *>ge by r$-hot p>ticles ( c>bon4 ,?is results 9 loss ( p[]1 & is fir/ notic$ by inability to climb /eep hills t 7 =m]ly negotiat$ ) ease4 ,m5tion mu/ also be made ( ! great claim = sil5ce ( runn+ ( sleeve valve eng9es1 & ?is is ?or\ghly ju/ifi$ ) high-class eng9es ( ! sleeve valve type1 provid$ !y are 9 ! h&s ( skill$ driv]s4 ,9 unskill$ h&s "o f9ds t ! poppet valve is saf]1 & w /& m knock+ ab\t )\t mu* increase 9 noise result+4 ,rot>y valves h fall5 into disuse on acc\nt ( ! difficulty ( keep+ !m gas-tight4 ,!re is no?+ to *oose betwe5 poppet & sleeve valves on ! score ( economy 9 runn+4 ,economy & ,durability4--,a good mod]n petrol eng9e ( reasonable size--say ov] #c 94 bore--w give "o brake horse-p[] = an h\r f ! consumption ( two-?irds ( a p9t ( petrol4 ,?is means t an eng9e giv+ #ab horse-p[] on ! brake w\ld use a gallon ( petrol e h\r4 ,b economy 9 petrol consumption is n ! only desirable feature ( a petrol eng9e4 ,!re mu/ be economy 9 lubricat+ oil & 9 co/ ( replacem5ts or repairs4 ,n[adays ! t5d5cy ) high grade /eel alloys & o!r mod]n metals ( high /r5g? & durability is to cut ev]y?+ d[n to its m9imum size ) a view to r$uc+ ! co/ ( production4 ,?is (t5 leads to _m s]i\s tr\bles 9 runn+ on ! road4 ,9 *oos+ an eng9e "o %\ld c>efully exam9e su* po9ts z provision = we> & adju/m5t1 /r5g? & rigidity1 & :e!r ! eng9e impresses "o ) a s5se ( its durability & also its g5]al accessibility4 ,,*apt] ,x ,,two-,,/roke ,,eng9es ,9 ! two-/roke type ( petrol eng9e ! cycle ( op]ations is complet$ 9 two work+ /rokes ( ! pi/on in/ead ( ! f\r requir$ by ! 8,otto0 cycle2 !re is ?us "o explosion or p[] /roke 9 e revolution ( ! crank%aft4 ,!oretically ?is repres5ts a great advance ov] ! 8,otto0 cycle1 b difficulties & complications arise 9 ! practical c>ry+ out ( ! cycle4 ,! cycle on :i* x is desir$ to op]ate ! eng9e is3 #a/ /roke--,compression2 #bnd /roke--,explosion4 ,! *>ge w\ld be introduc$ on ! compression /roke & exhau/$ t[>ds ! end ( ! explosion /roke4 ,n[ ! *>ge ( gas requir$ by ! eng9e consi/s ( a mixture ( petrol vap\r & air1 & x mu/ ei!r be suck$ 9 or pu%$ 9 "u pressure4 ,9 ! 8,otto0 cycle ! *>ge is suck$ 91 & 9 ! two-/roke cycle x is deliv]$ to ! cyl9d] "u pressure2 h5ce 9 ! two-/roke cycle "s =m ( pump is requir$ :i* w suck 9 ! *>ge ( air & gas1 compress x a small am\nt1 & deliv] x to ! work+ cyl9d] at a pressure ( #e or #f lb4 p] squ>e in* above atmosph]ic pressure4 ,?is is :]e ! complications comm5ce2 if we fit a sep>ate pump = ea* cyl9d]1 :i* is :at w\ld g5]ally be done1 or if we made "o pump s]ve = two cyl9d]s1 we h to provide pump cyl9d]s1 pi/ons1 rods & valves1 & !re=e !re is practically no ga9 ov] ! f\r-/roke eng9e4 ,h5ce x is t inv5tors all try to avoid ! use ( a sep>ate *>g+ pump & turn _! att5tion to ! production ( an eng9e 9 :i* "o or m ( ! exi/+ portions is made to s]ve z a pump = *>g+ ! work+ cyl9d] or cyl9d]s ) gas4 ,a fav\rite & fairly successful device is to make ! crank*amb] gas-tight & use x z ! cyl9d] ( ! pump1 ! und]side ( ! eng9e pi/on !n =m+ ! pump pi/on :i* draws ! *>ge f ! c>burettor into ! crank*amb] on its up/roke & compresses x on its d[n/roke1 deliv]+ x to ! work+ cyl9d] ?r\gh ! inlet port z soon z ! pi/on has uncov]$ x by its d[nw>d movem5t4 ,,fig4 #fc4--,,two ,,port ,,type ,,( ,,two-,,/roke ,,eng9e ,,) ,,crankcase ,,compression4 ,!re is no exhau/ valve1 z ! pi/on uncov]s ! exhau/ ports a little be=e ! inlet ports are op5$4 ,to prev5t ! new *>ge escap+ directly across ! top ( ! pi/on f ! inlet ports to ! exhau/ ports1 a deflector is fitt$ on ! top ( ! pi/on equal 9 height to ! height ( ! exhau/ op5+ & situat$ imm$iately 9 front ( & fac+ ! inlet ports4 ,a two-/roke eng9e ( ! type ref]r$ to is %[n diagrammatically 9 ,fig4 #fc4 ,e is ! gas-tight crank*amb]1 ^u :i* ! wat]-cool$ cyl9d] ,a is m\nt$ 9 ! usual mann] & fix$ by /uds or bolts4 ,! pi/on ,p c>ries ! deflector ,h1 :i* is equal 9 height to ! height ( ! exhau/ op5+ ,g4 ,! pi/on r+s are prev5t$ f turn+ by p9s s arrang$ t ! jo9t ( ! r+s does n pass across ! ports4 ,! connect+ rod ,d is ( usual =m1 & also ! crank%aft ,c4 ,! c>burettor1 or induction pipe lead+ f ! c>burettor1 w\ld be atta*$ to ! flange ,l1 & ! automatic valve ,f controls ! admission ( gase\s mixture f ! c>burettor to ! crank*amb]4 ,! inlet ports ,n are (t5 only half ! height ( ! exhau/ ports4 ,on ! up/roke ( ! pi/on a p>tial vacuum w be =m$ 9 ! air-tight crank*amb]1 :i* w all[ ! atmosph]ic pressure to =ce op5 ! valve ,f aga9/ ! pressure ( ! spr+ & enable ! air to fl[ into ! crank*amb] ?r\gh ! c>burettor & induction pipe1 c>ry+ ! *>ge ( petrol vap\r ) x4 ,we mu/ note1 h[ev]1 t no vacuum c be =m$ until ! port ,n has be5 cov]$ up by ! pi/on1 s t a portion ( ! /roke is idle4 ,on ! d[nw>d /roke ( ! pi/on ! *>ge 9 ! crank*amb] is compress$1 & z soon z ! pi/on uncov]s ! ports ,n ! *>ge f ! crank*amb] fl[s up into ! work+ cyl9d]1 displac+ ! burnt gases z x comes into ! cyl9d]4 ,exactly :at happ5s next x is difficult to say2 ! probability is t ?is new *>ge rises 9 ! cyl9d] a %ort di/ance 7b n a suffici5t am\nt to displace all ! dead gases f ! top end ( ! cyl9d]7 & t "s ( x gets squeez$ out ( ! exhau/ op5+ z ! pi/on rises & be=e x has _h "t to cov] ! exhau/ ports4 ,?us1 ow+ to ! idle portion ( ! /roke dur+ admission to ! crank*amb] & to ! l[ compression pressure adopt$ 9 ! crank*amb]1 ! pump+ portion ( ! eng9e has :at is t]m$ a v l[ volumetric effici5cy4 ,x c be prov$ t ?is type ( eng9e :i* endeav\rs to draw suffici5t gas to fill its work+ cyl9d] into ! crank*amb] by means ( a pi/on hav+ only ! same diamet] z ! diamet] ( ! work+ cyl9d] itself1 & :i* _c avoid "s idle movem5t dur+ ! op]ation toge!r ) fur!r loss f ! exhau/ op5+1 is incapable ( reta9+ m ?an a little ov] "o-half a cyl9d] full ( fre% combu/ible gas at ! in/ant :5 compression comm5ces2 ! rema9d] ( ! cont5ts mu/ be dead exhau/ gas4 ,?us1 ev5 all[+ = ! d\ble numb] ( p[] impulses result+ f ! use ( ! two-/roke cycle1 x is difficult to see h[ ?is =m ( eng9e c\ld ev] give m ?an ab\t "o & a qu>t] times ! p[] ( a f\r-/roke eng9e hav+ ! same bore & /roke ev5 :5 ! _m difficulties exp]i5c$ 9 ! practical work+ ( two-/roke eng9es h be5 ov]come4 ,to use a high compression pressure 9 ! crank*amb] w\ld increase ! volumetric effici5cy1 b w\ld result 9 lo/ "w dur+ ! pump+ process1 besides be+ undesirable at ! deliv]y /age ( ! process2 x is mu* bett] = ! transf] ( ! gases to take place z g5tly z possible4 ,if too high a deliv]y pressure is us$ ! fre% gas w ent] 9 a %>p gu/ & get badly contam9at$ by mixture ) ! f\l exhau/ products in/ead ( g5tly displac+ !m 9 bulk4 ,! use ( an automatic valve is v desirable = ! gas inlet to ! crank*amb]1 b un=tunately x limits ! spe$ ( ! eng9e & also its flexibility or ability to pull well at all spe$s4 ,an eng9e ) an automatic valve runs be/ at t spe$ = :i* ! t5sion ( ! spr+ is mo/ suitable4 ,if ! spr+ is weak ! spe$ w be l[4 ,tight5+ ! t5sion on ! spr+ w all[ ! eng9e to spe$ up1 b w prev5t x runn+ well at l[ spe$s4 ,at high spe$s & ) correspond+ly high t5sion ! valve does n give en\gh op5+1 & !re=e limits ! p[] ( ! eng9e4 ,x w1 !re=e1 readily be se5 t :5 a two-/roke eng9e ) automatic inlet valves is pitt$ aga9/ a f\r-/roke eng9e ) me*anically-op]at$ inlet valves1 ! comp>ison is unfair to ! two-/roke cycle4 ,) ! position & arrangem5t ( ports %[n 9 ! draw+s1 "o mu/ h a deflector on ! pi/on head to prev5t excessive loss ( fre% gas ?r\gh ! exhau/ op5+4 ,aft] ! eng9e has be5 runn+ = "s "t at a high spe$ ?is deflector becomes v hot1 & z a g5]al rule ! cool+ effect ( ! incom+ gases is n suffici5t to prev5t x atta9+ a r$ heat on ! compression /roke1 ?us ignit+ ! *>ge be=e ! pi/on rea*es ! top ( ! /roke4 ,?is defect1 :i* is call$ pre-ignition1 causes ! eng9e to knock1 & results 9 a loss ( p[]2 x may be p>tly ov]come by admitt+ lubricat+ oil ) ! *>ge1 ! oil !n s]v+ to cool ! deflector z ! *>ge ent]s ! cyl9d]4 ,at high eng9e spe$s !re is great risk ( ! hot exhau/ gases 9 ! work+ cyl9d] sett+ fire to ! incom+ *>ge 9 ! inlet ports1 ?us caus+ backfir+ into ! crank*amb]4 ,to avoid all possibility ( backfire1 "s =m ( air scav5g+ mu/ be adopt$1 b ! g5]al arrangem5t ( ?is =m ( two-/roke eng9e does n l5d itself to su* an addition--x w\ld m]ely r$uce /ill fur!r ! quantity ( gas rea*+ ! cyl9d]4 ,a difficulty t is peculi> to multi-cyl9d] eng9es ( ! two-/roke type arises f ! use ( op5 exhau/ ports4 ,! sev]al cyl9d]s g5]ally dis*>ge _! exhau/ gases into a common exhau/ pipe or box1 s t if "o cyl9d] happ5s to be miss+ fire ! exhau/ f ano!r cyl9d] may set fire to ! wa/$ *>ge--?is is usually ref]r$ to z fla%+-back f ! exhau/ & results 9 irregul> & spasmodic knock+4 ,x w be cle> f ! =ego+ t ?is cycle ( op]ations1 :i* is s attractive f ! !oretical po9t ( view1 is n by any means s enc\rag+ f ! practical /&po9t1 z _m inv5tors h discov]$4 ,! difficulties & failures ( ! e>ly inv5tors :i* 7 s disc\rag+ = !m h only enc\rag$ _! successors & spurr$ !m on to fur!r ef=ts4 ,aft] a "t ! attempt to produce a simple two-/roke eng9e 0 ab&on$ g5]ally1 & inv5tors turn$ _! att5tion to improv$ =ms ( two-/roke eng9es1 "s ( :i* 7 v co/ly & complicat$1 & none ( :i* h surviv$ = motor-c> purposes4 ,! writ] ( ?is volume became int]e/$ 9 ! problem ( ! two-/roke 9 connexion ) "o ( ^! inv5tions = an improv$ eng9e1 & at a lat] /age pat5t$ & design$ an improv$ eng9e ( ! two-/roke air scav5g+ v>iety1 :i* by t "t _h become a recogniz$ type ( two-/roke eng9e4 ,?is eng9e 0 con/ruct$ & exhibit$ at "o ( ! motor %[s held 9 ,london "s ye>s ago4 ,a va/ am\nt ( exp]im5tal & rese>* "w 0 c>ri$ out on x by ! writ]1 b ! "w _h to be ab&on$ :5 incomplete ow+ to ! ,syndicate :i* f9anc$ ! v5ture hav+ exhau/$ its res\rces4 ,! promot]s ( ! ,syndicate 7 anxi\s to produce an eng9e t w\ld give d\ble ! p[] ( a f\r-/roke eng9e1 b _! e>ly attempts 7 n at all successful4 ,"o ( _! f\r-cyl9d] eng9es1 :i* w\ld h be5 rat$ at #ce horse-p[] on ! f\r-/roke cycle1 only gave #ab brake horse-p[] :5 te/$ by ! writ]4 ,! eng9e design$ by ! writ]1 :i* we may call ! ,kean two-/roke eng9e1 w\ld h be5 rat$ at #be horse-p[] on ! f\r-/roke cycle1 & gave approximately #ce brake horse-p[]4 ,al?\gh ?is result 0 excell5t1 s mu* advance _h be5 made 9 ! f\r-/roke eng9e t x did n q come up to ! be/ results obta9$ on t sy/em1 & h5ce we 7 unable to %[ any m>k$ advantage to be ga9$ f its adoption4 ,my exp]im5ts cle>ly po9t$ out ! road to fur!r success1 b ow+ to ! p>tial failure ( my attempt to beat ! f\r-/roke eng9e we c\ld n influ5ce suffici5t capital to reorganize & recon/ruct ! ,syndicate4 ,my eng9e _h n be5 design$ to secure a high spe$ ( rotation b r = /r5g? & durability1 b x exce$$ my expectations by turn+ up to #a1ejj revolutions p] m9ute4 ,! f\r-/roke _h1 h[ev]1 got well ahead ( me by t "t1 & #b1jjj 0 becom+ common = x1 h5ce ,i 0 heavily h&icapp$ 9 ! race = horse-p[]4 ,illu/ration3 ,,fig4 #fd4--;,,diagrammatic ,,sket* ,,%[+ ,,h[ ,,! ,,duplex ,,type ,,( ,,two-,,/roke ,,eng9e ,,op]ates ,,) ,,air ,,scav5g+4 ,a description ( my eng9e w probably prove ( int]e/4 ,to und]/& ! pr9ciple ( ! eng9e we mu/ turn to ! diagrammatic sectional view ( ,fig4 #fd4 ,in/ead ( us+ ! crank*amb] ( ! eng9e z a gas pump1 ?is type ( eng9e has a duplex pi/on1 & ! pump *amb] is =m$ by an annul> ext5sion ( ! ma9 eng9e cyl9d]4 ,at fir/ sight "o w\ld say ?is result$ 9 a v high eng9e1 b z a matt] ( fact ! increase 9 height is n m ?an ab\t #be p] c5t4 9 ! cyl9d]s1 & !re is no diff]5ce 9 ! crank*amb] height to t ( a f\r-/roke eng9e4 ,! out/&+ feature ( ! inv5tion is ! provision ( a pump pi/on ( l>g] effective diamet] ?an ! ma9 pi/on & ! arrangem5t ( transf] pipes by :i* "o pump fe$s its neighb\r's p[] cyl9d]1 & vice v]sa4 ,^! are ! basis ( ! inv5tion1 & 7 be+ us$ a long "t be=e ! writ] _h ev5 he>d ( ?is type ( eng9e1 b x 0 left = him to seize ^u _! capabilities & correctly proportion ! area ( ! annulus ) respect to ! ma9 eng9e pi/on4 ,a c>eful /udy ( ! two-/roke problem reveal$ ! inh]5t defect ( ! l[ volumetric effici5cy & ! trem5d\s possibilities ( hav+ an unlimit$ volume = ! pump *amb] by simply increas+ ! area ( ! l[] or annul> pi/on4 ,!n foll[$ ! writ]'s attempt to tackle ! out/&+ practical difficulties enum]at$ above4 ,! eng9es already employ$ air scav5g+1 b c\ld n really use x effectively until prop] proportions _h be5 fix$ ^u = ! respective pipes1 valves1 & ports4 ,! cycle ( op]ations is z foll[s3--,on ! d[n/roke ( ,no4 #a pi/on ! annul> portion draws a *>ge ( gas f ! c>burettor into ! annul> *amb] ,d#a 7,fig4 #fd7 ?r\gh ! inlet valve ,b#a & at ! same "t pure air is drawn into ! transf] pipe by ! valve ,a#b4 ,on ! up/roke ! *>ges ( air & gas are compress$ into ! transf] pipe1 & z soon z ! pi/on ,p#b uncov]s ! inlet ports ! air & gas ent] ! work+ cyl9d]4 ,9 my eng9e ,i us$ a relatively high compression pressure = ! transf] ( ! *>ge & curv$ ! inlet ports up t[>ds ! head ( ! cyl9d] z %[n4 ,! head ( cyl9d] ,i made curv$1 & ! exhau/ ports 7 c>efully r\nd$ & curv$ also4 ,! deflector on ! head ( ! pi/on ,i incl9$1 to curl ! gases back aga9/ ! wall ( ! cyl9d]1 & ,i r$uc$ ! height ( ! deflector to t ( ! inlet port 7in/ead ( ! exhau/ port74 ,my ultimate aim 0 to aboli% ! deflector entirely by suitably %ap+ ! inlet ports1 & ,i e/imat$ t ! pa? ( ! gases w\ld be 9 ! direction ( ! arr[s4 ,! object ( rais+ ! compression pressure 9 ! l[] cyl9d] 0 tw(old4 ,fir/ ( all ,i aim$ at an increase ( volumetric effici5cy !re1 & secondly ,i hop$ to propel ! scav5g+ air & ! new *>ge "r up to ! head ( ! cyl9d] & s cle> out all ! dead gases4 ,!n by suitably curv+ ! head ( ! cyl9d] ,i expect$ to compel ! scav5g+ air to keep go+ ahead ( ! gase\s mixture & curl r\nd & d[n1 !n foll[+ ! exhau/ gases out ( ! exhau/ port4 ,my ef=ts 9 ?is direction 7 v un=tunately fru/rat$ to a l>ge ext5t by ! fact t ! cyl9d]s ( my eng9e _h already be5 ca/ be=e ,i fully realiz$ ! trem5d\s importance ( curv+ ! cyl9d] head & giv+ a v /eep incl9ation to ! inlet ports4 ,we did our be/ to rectify matt]s 9 ! ma*9+ & f9i%+ /ages1 b any eng9e] w und]/& ! limitations n[ impos$ ^u u4 ,x 0 impossible to get new cyl9d]s ca/ ow+ to lack ( "t & funds1 z we 7 int5d+ to exhibit ! complet$ eng9e4 ,?us ,i _c say t my ideas 7 ev] giv5 a really satisfactory te/2 ! inlet ports 7 curv$ & incl9$ & ! cyl9d] head 0 r\nd$ (f1 b n to su* an ext5t t ,i c feel c]ta9 no fur!r improvem5t c\ld ev] be made 9 ^? directions4 ,o!r improvem5ts :i* ,i introduc$ 7 an improv$ automatic inlet valve = ! gases1 :i* 0 fitt$ inside ! induction pipe & ^: spr+ t5sion c\ld be adju/$ :ile ! eng9e 0 runn+ )\t lett+ any air leak into ! induction pipe2 also an improv$ air scav5g+ valve1 :i* c\ld be set to give ! full am\nt ( air to ! eng9e & yet be controll$ f ! da%bo>d ( ! c> to give any desir$ quantity ( scav5g+ air f no air up to full air4 ,v l>ge inlet valves 7 fitt$1 b :5 indicator diagrams 7 ev5tually obta9$ f ! eng9e !y %[$ t !y 7 n ne>ly l>ge en\gh & t ! c>burettor op5+ 0 too re/rict$1 ?us cutt+ d[n ! p[] 7& v likely ! spe$7 ( ! eng9e by probably ov] #be p] c5t4 ,high t5sion magneto ignition 0 fitt$ & !rmo-syphon cool+4 ,arrangem5ts 7 made to c>ry #hj lb4 ( wat] 9 ! sy/em1 s t ! eng9e nev] %[$ any t5d5cy to boil ev5 :5 ! c> _h be5 runn+ = long p]iods on ! l[ ge>4 ,a pump 0 aft]w>ds fitt$1 b x did n effect ! cool+ ( ! wat] any bett] ?an ! natural circulation1 :i* 0 q satisfactory4 ,! range ( spe$ 0 f #aej revolutions p] m9ute up to #a1ejj revolutions p] m9ute2 ! l[] figure is v good inde$1 & c be attribut$ to ! l>ge numb] ( impulses obta9$ due to ! two-/roke cycle4 ,at ! highe/ spe$ ! crank%aft receiv$ #f1jjj impulses p] m9ute1 or equival5t to a f\r-/roke eng9e runn+ at #c1jjj revolutions p] m9ute4 ,! effective pressure 9 ! cyl9d] 01 h[ev]1 only j ov] #dj p\nds p] squ>e in*1 due to ! ?rottl+ at inlet already expla9$4 ,9 a f\r-/roke eng9e we w\ld expect j d\ble t figure4 ,! extraord9>y ?+ ab\t ?is 0 t1 "u heavy load1 :5 ! spe$ 0 br\ght d[n to ab\t #cjj revolutions p] m9ute1 ! effective pressure _h ris5 to ne>ly #bjj lb4 p] squ>e in*1 b ?is appe>s to be due to imp]fect scav5g+ 7or cleans+7 ( ! cyl9d] "u ^! conditions4 ,! "q ( sil5c+ ! exhau/ f ! eng9e _h caus$ me "s difficulty 9 ! e>li] exp]im5ts1 s t ,i n[ tackl$ ?is problem & design$ a special =m ( sil5c] 9 :i* ! gases 7 fir/ exp&$ to remove _! pressure & !n aft]w>ds _! velocity 0 tak5 up )\t %ock4 ,?is answ]$ s well t a cut-out made no diff]5ce :atev]1 & on tak+ diagrams ) ! optical indicator ,i discov]$ t ! exhau/+ process 0 divid$ into equal p]iods ( slight pressure & slight vacuum ) an av]age ( z]o pressure 7j atmosph]ic74 ,we h se5 9 ! e>li] "p ( ?is *apt] h[ ! fitt+ ( automatic inlet valves is liable to hamp] ! eng9e & r$uce its flexibility1 & ?is impress$ me v mu* ) ! e>li] eng9es s t at "o "t ,i adopt$ dual spr+s = ! inlet valves4 ,^! spr+s 7 m\nt$ "o above ! o!r1 ! l[] "o be+ mu* /iff] ?an ! upp] "o4 ,! idea ( ! inv5tion 0 t ! weak spr+s w\ld s]ve = sl[ runn+ & all loads up to say half ! lift ( ! valve1 & !n ! /iff] spr+s w\ld secure correct action at high spe$s4 ,fur!r ?an ?is1 ,i _h !m all c\pl$ on a b> :i* 0 controll$ f ! driv]'s seat1 & by means ( :i* ,i c\ld cut out ! weak] spr+s or r$uce _! effect at w4 ,x c]ta9ly answ]$ well 9 ! old] eng9es1 b my new eng9e1 %[n 9 ,fig4 #fe1 0 s satisfactory t ,i ab&on$ ! idea4 ,ab\t five diff]5t sy/ems ( lubrication 7 exp]im5t$ ) & _m lubricat+ oils4 ,f9ally1 =c$ lubrication 0 employ$ = all ! be>+s & a drip sight-fe$ = ! pi/ons4 ,illu/ration3 ,,fig4 #fe4--;,,g5]al ,,arrangem5t ,,( ,,! 8,,kean0 ,,f\r-,,cyl9d] ,,high ,,spe$ ,,high ,,compression ,,duplex ,,two-,,/roke ,,eng9e ,,employ+ ,,air ,,scav5g+4 ,,9 ,,?is ,,eng9e ,,!re ,,is ,,no ,,crank*amb] ,,compression4 ,mu* tr\ble 0 caus$ at "o "t 9 ! new eng9e by knock+ ( v>i\s k9ds1 & _m h\rs 7 sp5t 9 locat+ ^! tr\bles & cur+ !m4 ,! fir/ k9d ( knock+ 0 mo/ viol5t & almo/ made "o hold "o's brea? 9 anticipation ( see+ p>ts ( ! eng9e g skyw>ds4 ,?is turn$ out to be p>tial seizure ( a pi/on ow+ to a h>d spot 9 ! cyl9d]4 ,aft] cur+ ?is1 g5]al knock+ f all cyl9d]s began1 & 0 f\nd to result f worn gudgeon p9s4 ,^! _h be5 mild /eel & case-h>d5$2 !y 7 disc>d$ = ,ubas /eel ( slightly l>g] diamet]1 & ?is tr\ble disappe>$4 ,!n pre-ignition 0 discov]$4 ,:5 ! magneto 0 swit*$ (f ! eng9e sl[$ d[n & ne>ly /opp$1 !n began to run on aga91 knock+ & hamm]+ 9 a mo/ diabolical mann]4 ,all cyl9d]s 7 tak5 (f aga91 all p>ts gr\nd up1 & corn]s well r\nd$ (f1 b /ill x cont9u$4 ,at fir/ x seem$ to be due to ! deflectors1 b on sev]al v c>eful exam9ations 7:i* ( c\rse meant dismantl+ ! :ole eng9e e "t & remov+ ! cyl9d]s7 no trace ( ov]heat+ or burn+ c\ld be f\nd on ^! or any:]e else 9 ! int]ior ( ! cyl9d]4 ,!n ! tr\ble 0 trac$ to ! electrodes ( ! sp>k+ plugs4 ,?is 0 foll[$ by two or ?ree weeks' cont9u\s exp]im5ts on fitt+ diff]5t types ( plugs1 & ! same type ( plug 0 tri$ 9 f\r diff]5t positions inside ! cyl9d]4 ,!n ! device ( fitt+ ! plugs to an adapt] & s keep+ !m at ! top ( a small hole in/ead ( project+ into ! cyl9d]s 0 tri$4 ,!y /ill %[$ signs ( ov]heat+1 & /range to say no loss ( p[] or flexibility 0 noticeable4 ,f9ally1 ,i fitt$ a wat] tank on ! da%bo>d & all[$ ! eng9e to suck wat] into ! induction pipe :ile x drew its mixture f ! c>burettor 9 ! usual mann]4 ,i _h previ\sly fitt$ sep>ate drip-fe$ ( wat] to ! air scav5g+ valves ) a view to effect+ cool+ ( ! eng9e1 b ab&on$ x ow+ to lack ( results4 ,v soon ,i discov]$ t = e gallon ( petrol ! eng9e consum$ ,i c\ld let x take ne>ly half a gallon ( wat] into ! induction pipe4 ,! eng9e ran mu* quiet] & v smoo?ly1 & = a "t ,i ?\ght ,i _h succe$$1 al?\gh ! wat] gave me tr\ble 9 re/>t+ if ,i happ5$ to /op ! eng9e :ile x 0 9 use4 ,x meant t ! wat] _h to be %ut (f "s m9utes be=e ! eng9e 0 go+ to be /opp$4 ,! day aft] ,i ?\ght ,i _h effect$ a cure = ! pre-ignition int]mitt5t knock+ began1 & !re 0 also g5]al knock+ always = a second or two :5 accel]at+ quickly "u load4 ,aft] mu* loss ( "t & ! exp5diture ( a l>ge sum ( money on exp]im5ts1 ,i p]suad$ ! ,syndicate to let me take "s diagrams f ! eng9e ) an optical indicator1 & ev5tually aft] n9e mon?s !y cons5t$1 b !y w\ld n agree to my tak+ ! eng9e out ( ! *assis & putt+ x on ! b5* = a prop] p[] te/4 ,!re=e my diagrams 7 tak5 :ile ! eng9e 0 9 ! g>age 9 its *assis1 & ! load 0 appli$ by ! propellor %aft brake1 ! %aft itself be+ )drawn4 ,anyone :o has attempt$ ev5 9 a well-equipp$ laboratory & ) ! aid ( a prop] brake to take diagrams f a petrol eng9e :5 ! indicator is driv5 by a flexible %aft1 w und]/& & appreciate my "w 9 secur+ ?irty photographic records "u z _m conditions ( load & spe$4 ,aft] c>efully analyz+ my diagrams1 ,i came to ! conclusion t ! int]mitt5t knock+ 0 und\bt$ly fla%+ back f ! exhau/1 & ! accel]ation knock+ 0 due to a cu%ion ( hot gas :i* accumulat$ 9 ! head end ( ! cyl9d] at times :5 ! eng9e spe$ 0 l[ & ! load on ! eng9e 0 heavy4 ,hav+ expla9$ ^! ?+s to ! ,syndicate & po9t$ out ! ne$ = /ill l>g] valves1 !y set ab\t attempt+ to raise fre% capital = ! f9al attempt at success4 ,!y 7 n successful1 & up to ! pres5t no?+ m has be5 done4 ,! ,syndicate 0 w\nd up1 ! memb]s drift$ ap>t1 & ! pat5ts 7 all[$ to lapse4 ,! eng9e & *assis 7 ev5tually sold1 & are /ill do+ good s]vice some:]e 9 ! ,nor? ( ,engl&4 ,meantime ! writ] has n re/$1 b has /eadily =mulat$ 8 ideas = ! improvem5t ( ! eng9e1 :i* h result$ 9 ! secur+ ( a fre% pat5t e>ly ?is ye>4 ,9 ! new eng9e ! *>ge ent]s at ! head end ( ! cyl9d]1 !re is a special transv]se combu/ion *amb]1 & _m improvem5ts are introduc$ 9 ! scav5g+ & fl[ ( gases2 also !re is no deflector at all on ! pi/on head4 ,funds h n yet be5 secur$ to enable an exp]im5tal eng9e to be con/ruct$1 b x is to be hop$ !y w be =?com+1 = ! b5efit ( ! motor-c> indu/ry g5]ally1 z ! future und\bt$ly lies ) ! two-/roke4 ,dur+ ! :ole ( ?is "t ! writ] 0 engag$ z ,*ief ,assi/ant 9 ! ,eng9e]+ ,dep>tm5t ( ,le$s ,univ]sity1 be+ 9 *>ge ( ! exp]im5tal "w ( ! /ud5ts 9 ! laboratories !re4 ,_m ( ! draw+s 7 made by /ud5ts 9 _! vacation1 & ! writ] is greatly indebt$ to 8 fri5d1 ,pr(essor ,john ,goodman1 = s k9dly all[+ him ! necess>y fre$om dur+ vacation times :5 !re is (t5 mu* miscellane\s "w t requires att5tion4 ,be=e clos+ ?is *apt] "o may add a few words on c>buration & ignition = two-/roke eng9es4 ,a f\r-cyl9d] two-/roke eng9e %\ld h cranks at "r angles to secure ! maximum torque on ! %aft4 ,look$ at 9 end view ! cranks =m ! f\r arms ( a cross & ?us f\r impulses are giv5 e revolution1 b z ! ord9>y magneto only gives two sp>ks 9 e revolution x mu/ be driv5 at twice ! crank%aft spe$4 ,?is puts a great /ra9 on ! ma*9e at top spe$1 & also on ! insulation ( ! w9d+s & ! plugs1 s t ! plugs require con/ant att5tion4 ,magneto tr\bles 7 f\nd to be elim9at$ by ! use ( ! special rac+ patt]n magneto suppli$ by "s manufactur]s & ! *oice ( high grade sp>k+ plugs4 ,c>buration tr\bles 7 n s easily dealt )4 ,a multi-cyl9d] two-/roke eng9e %\ld und\bt$ly h a multiple jet c>burettor & "s =m ( h&-controll$ extra-air inlet valve on ! induction pipe2 also ! mix+ *amb] ( ! c>burettor %\ld be wat]-jacket$ by hot wat]4 ,x 0 also f\nd necess>y to fit a hot wat]-jacket r\nd a portion ( ! induction pipe1 z ! dem& = petrol vap\r 0 s great & ! rate ( evaporation s high t fro/ readily =m$ on ! induction pipe unless ! wea!r 0 v w>m4 ,! two-/roke eng9e requires its petrol mu* fa/] ?an ! f\r-/roke1 s t ! float ( ! c>burettor %\ld be delicately balanc$ & ! height ( ! petrol 9 ! jet %\ld be q level ) ! top ( ! orifice1 al?\gh ?is (t5 leads to flood+4 ,review+ ! description ( :at we h designat$ ! ,kean two-/roke eng9e1 we may sum up ! results ( ^! exp]im5ts by say+ t ! eng9e c\ld h develop$ consid]ably m p[] ?an x did _h diagrams be5 tak5 f x 9 ! fir/ in/ance & ! sev]e ?rottl+ 9 ! c>burettor & automatic inlet valves be5 discov]$2 moreov]1 ! fla%+ back f ! exhau/ w\ld h be5 locat$ mu* soon] & probably cur$ by a re-arrangem5t ( ! exhau/ manifold4 ,if ! exhau/ manifold _h be5 arrang$ s t !re 0 a sep>ate bran* = at lea/ ea* pair ( cyl9d]s1 x w\ld v likely h be5 /opp$1 or at any rate greatly r$uc$4 ,b :at c\ld n h be5 alt]$ 0 ! accel]ation knock+4 ,x mu/ n be imag9$ because ,i h be5 v frank 9 ! criticism ( my own "w t ! eng9e 0 a failure2 x 0 a great success1 b n suffici5tly successful to repres5t an improvem5t on ! be/ f\r-/roke practice4 ,! c> ran well1 0 v reliable & effici5t 9 petrol consumption2 ! eng9e 0 quiet & extremely flexible2 b x _h "o v objectionable feature 9 t e "t y press$ ! accel]ator p$al d[n %>ply1 ei!r to put on a spurt = ! purpose ( pass+ sl[] traffic or 9 ru%+ a %ort gradi5t1 a peculi> knock+ or hamm]+ arose f ! eng9e cyl9d]s--?is is :at ,i describe z accel]ation knock+ & mu/ n be confus$ ) ! knock+ or hamm]+ ( a f\r-/roke eng9e :5 lab\r+ on a gradi5t4 ,my eng9e w\ld be full ( life all ! "t x 0 knock+ l ?is1 & gradually z ! spe$ increas$ ! noise w\ld ease-(f1 ev5 ?\gh no *ange ( ge> _h be5 made4 ,! diagrams prov$ to me t ?is knock+ 0 due to pre-ignition caus$ by a cu%ion ( hot gases rema9+ 9 ! top ( ! work+ cyl9d]1 & 9 my op9ion no alt]ation ( ! ports or cyl9d] head w\ld h influ5c$ ?is defect to any m>k$ ext5t2 !re=e ,i %\ld nev] attempt aga9 to fe$ ! new *>ge 9 at ! bottom end ( ! cyl9d] ( a two-/roke eng9e if ,i wi%$ to obta9 ! maximum am\nt ( p[] f x4 ,x seems to me t o!r p mu/ also h be5 impress$ ) simil> misgiv+s1 = 9 "o or two types ( eng9e us+ crank*amb] compression we see a special attempt made to ov]come x1 al?\gh ! me?od adopt$ leads to a r undesirable arrangem5t ( ! eng9e me*anism4 ,9 ! type ( eng9e ,i ref] to ! *>ge may be drawn into ! crank*amb] 9 ! usual mann]1 if desir$1 b ! work+ cyl9d] is a ca/+ ) two bores hav+ two sep>ate pi/ons & a common combu/ion *amb]4 ,! *>ge ent]s above "o pi/on :ile ! crank is on its bottom dead-c5tre & is exhau/$ f ! space above ! o!r pi/on simultane\sly1 & ! pa? ( ! gases is f ! inlet port up to ! top ( ,no4 7#a7 bore1 !n d[n to ,no4 7#b7 bore1 & out ( ! exhau/4 ,?is ensures t !re %all be no cu%ion ( hot exhau/ gases left 9 ! combu/ion *amb] 7or top end ( ! cyl9d]74 ,^! eng9es h giv5 q good results1 & w\ld be mu* m ext5sively us$ b = ! fact t !re is d\ble compression to ov]come 9 />t+1 & _! runn+ torque1 due to ! numb] ( impulses giv5 to ! crank%aft1 is no bett] ?an a f\r-/roke eng9e4 ,fig4 #ff %[s ! arrangem5t ( ! cyl9d]s & ! pa? ( ! gases4 ,a#a & ,a#b are ! tw9 pi/ons work+ 9 ! wat]-jacket$ cyl9d] ca/+ ,b1 & hav+ ! common combu/ion *amb] ,c4 ,! connect+ rods may drive sep>ate cranks 9 opposite directions or bo? be c\pl$ toge!r & "w a s+le crank4 ,x w be se5 t 9 ?is type ( eng9e ! pi/on does n require any deflector4 ,! simple two-/roke eng9e describ$ at ! beg9n+ ( ?is *apt] is (t5 con/ruct$ 9 su* a =m t no automatic inlet valve is requir$ on ! crank*amb]4 ,9 ?is case ! induction pipe is connect$ to a ?ird set ( ports j bel[ & a little to "o side ( ! inlet ports to ! work+ cyl9d]1 & ^! are uncov]$ by ! pi/on t[>ds ! completion ( its up/roke1 ?us all[+ ! c>burett$ air to ent] ! crank*amb]4 ,su* an arrangem5t con/itutes a ?ree-port two-/roke eng9e1 :i* is ( c\rse less effici5t ?an a two-port eng9e ) automatic valve1 b has ! great m]it t x is entirely valveless1 & !re=e extremely simple & *eap to manufacture4 ,x is mu* us$ = motor boat "w1 bo? 9 ?is c\ntry & 9 ,am]ica1 on acc\nt ( its relatively l[ spe$ ( rotation4 ,illu/ration3 ,,fig4 #ff4--,,tw9-,,cyl9d] ,,two-,,/roke ,,eng9e ,,) ,,crank*amb] ,,compression4 ,,*apt] ,,xi ,,horse ,,p[] ,,& ,,! ,,indicator ,,diagram ,a book on 8,! ,petrol ,eng9e0 w\ld h>dly be complete )\t "s ref]5ce to horse-p[] & ! indicator diagram4 ,! foll[+ def9itions mu/ be c>efully /udi$4 ,"w4--,a =ce is said to d me*anical "w :5 x ov]comes a resi/ance 9 its own l9e ( action4 ,! l9e ( action ( a =ce is a l9e indicat+ ! direction 9 :i* ! =ce acts4 ,eng9e]s measure "w 9 foot-p\nd units4 ,! product obta9$ :5 we multiply ! magnitude ( ! =ce or resi/ance 79 p\nds7 by ! di/ance ?r\gh :i* x has act$ or be5 ov]come 7express$ 9 feet7 gives ! quantity ( "w done 9 foot-p\nds4 ,example3--,a =ce ( #ej lbs4 is ex]t$ 9 ov]com+ a resi/ance ?r\gh a di/ance ( #ab feet4 ,f9d ! "w done4 ,"w done ,=ce 79 lbs47 ,di/ance 79 ft47 #ej #ab #fjj ft4 lbs4 ,p[]4--,! rate at :i* "w is done is a measure ( ! p[] ex]t$4 ,"o horse-p[] is ex]t$ :5 #cc1jjj foot-p\nds ( "w are done 9 "o m9ute4 ,! "w done p] m9ute 79 ft4 lbs47 divid$ by #cc1jjj gives ! horse-p[] exp5d$4 ,example3--,to propel a motor-c> along a level road at a spe$ ( #cj miles an h\r requires a tractive ef=t or pull ( #gj lbs4 if ! vehicle weighs "o ton4 ,f9d ! horse-p[] requir$1 at ! road surface4 ,"w done p] m9ute 9 ft4 lbs4 ,horse-p[] ---------------------------------------- ---------------------- #cc1jjj ,=ce 79 lbs47 ,di/ance ?r\gh :i* x acts p] m9ute 79 ft74 ---------------------------------------- ---------------------------- #cc1jjj #gj #cj #ebhj ---------------------------- #fj #g #bfd ---------------------------- ------------- #ef #cc1jjj #ccj ,example3--,if ! c> 9 ! prec$+ example _h to climb a gradi5t :i* rose "o foot = e f\r feet trav]s$ by ! c>1 f9d ! additional horse-p[] ne$$ to keep up a spe$ ( #cj miles an h\r :ile climb+ ! gradi5t4 ,"h we h to raise a weight ( #a ton v]tically upw>ds ?r\gh a height equal to "o-f\r? ( ! road surface cov]$1 e m9ute4 ,additional ,horse-p[] requir$ 7#cj #ebhj #a7 #bbdj 7lbs47 7----------------- -7 ft4 p] m94 7 #fj #d7 ---------------------------------------- ---------------------------------------- ------ #cc1jjj #bbdj #ffj -------------------- #ddh #cc1jjj ,total ,horse-p[] to climb ! gradi5t ( #a 9 #d at #cj miles an h\r #ef #ddh #ejd ,brake ,horse-,p[]4--,! l5g? ( ! circumf]5ce or b\nd>y l9e ( a circle is #fbh times ! l5g? ( ! radius ( ! circle or #cad times ! l5g? ( its diamet]4 ,h5ce1 if an eng9e ex]ts a pull ( ,p lbs4 at ! end ( a brake arm ( l5g? ,r feet :5 x is ma9ta9+ a spe$ ( ,n revolutions p] m9ute 7we may imag9e ! brake to be fitt$ r\nd ! rim ( ! fly:eel71 we c calculate ! brake horse-p[] ?us3-- ,brake ,horse-,p[] or ,b4,h4,p4 ,"w done on ! brake p] m9ute 9 ft4 lbs4_/#cc1jjj ,h5ce ,b4,h4,p 7,pull at ! end ( ! brake arm 79 lbs477 7#fbh times ! radius ( ! arm 79 feet77 7! numb] ( revolutions made by ! eng9e 79 "o m9ute77_/#cc1jjj ,p #fbh ,r ,n_/#cc1jjj ,illu/ration3 ,,fig4 #fg4--,,petrol ,,eng9e ,,brake4 ,example3--,an eng9e be+ te/$ by a brake appli$ to ! fly:eel z %[n 9 ! sket* 7,fig4 #fg7 ex]ts a pull ( #ej lbs4 at a spe$ ( #b1jjj revolutions p] m9ute4 ,if ! l5g? ( brake arm is #cj in*es1 calculate ! brake horse-p[] develop$4 ,"w done p] m9ute #ej #fbh #cj_/ab #bjjj ft4 lbs4 ,b4,h4,p4 #ej #fbh #cj_/ab #bjjj_/cc1jjj #dge ,rat$ ,horse-,p[]4--,= taxation purposes ! ,treasury makes use ( a =mula = ! rat+ ( petrol eng9es accord+ to _! probable horse-p[]4 ,?is =mula is bas$ on a c]ta9 spe$ ( ! pi/on :i* 0 reg>d$ z a limit+ value "s ye>s ago 7:5 ! =mula 0 fir/ propos$7 & on ! atta9m5t ( a c]ta9 effective pressure 9 ! cyl9d]4 ,horse-p[] f ! ,treasury =mula #jd d#bn4 ,:]e d diamet] ( cyl9d] 9 in*es1 n numb] ( cyl9d]s4 ,) mod]n eng9es mu* great] horse-p[] is obta9$1 & a ne> approximation to ! true output is obta9$ by us+ :at is n[ kn[n z ! ,jo9t ,committee's =mula4 ,brake ,horse-,p[] #jdf n 7d s7 7d - #aah7 ,:]e d diamet] ( cyl9d] 9 in*es4 s l5g? ( pi/on's /roke 9 in*es4 ,?is =mula is only to be us$ 9 an attempt to pr$ict ! probable maximum horse-p[] :i* any eng9e w give4 ,x mu/ n be confus$ ) ! ord9>y brake horse-p[] =mula4 ,example3--,f9d ! probable maximum horse-p[] ( an eng9e hav+ f\r cyl9d]s ea* #c 94 bore & a pi/on /roke ( #d 94 ,:at w\ld be its horse-p[] = taxation purposes8 ,by ,jo9t ,committee's =mula-- ,b4,h4,p4 #jdf #d 7#c #d77c - #aah7 #ahd #g #ahb #bcce ,by ,treasury =mula-- ,b4,h4,p #jd #cb #d #jd #i #d #add ,indicat$ ,horse-,p[]4--,! horse-p[] :i* an indicator w\ld %[ z be+ develop$ inside ! cyl9d] ( a petrol eng9e1 above ! pi/on1 w\ld be call$ ! indicat$ horse-p[]1 & %\ld always "w out a great] numb] ?an ! brake horse-p[] or p[] available at ! eng9e fly:eel1 because "s ( ! p[] lib]at$ f ! combu/ion ( ! petrol )9 ! cyl9d] is lo/ 9 friction ( ! pi/on & be>+s4 ,! ,indicat$ ,horse-,p[] or ,i4,h4,p4 ,pe ,a ,l x ,ne_/#cc1jjj4 ,:]e ,pe mean effective pressure f ! diagram1 9 lbs4 p] sq4 in*4 ,a area ( pi/on 9 squ>e in*es #jghed 7diamet] ( cyl9d]7#b ,l l5g? ( /roke ( pi/on1 9 feet4 ,ne numb] ( p[] impulses p] m9ute deliv]$ to ! crank%aft4 ,s9ce a f\r-/roke eng9e gives "o p[] impulse to ! crank%aft 9 e two revolutions1 x foll[s t ,ne is equal to half ! numb] ( revolutions p] m9ute = a s+le-cyl9d] eng9e ( t type1 & twice ! numb] ( revolutions = a f\r-cyl9d] eng9e4 ,a f\r-cyl9d] two-/roke eng9e might be arrang$ to give ei!r two or f\r impulses p] revolution ( ! crank%aft--dep5d+ ^u ! arrangem5t ( ! cranks4 ,example3--,a f\r-cyl9d] f\r-/roke eng9e runs at a spe$ ( #b1jjj revolutions p] m9ute & ! mean-effective pressure 9 ! cyl9d]s is #ge lbs4 p] squ>e in*4 ,calculate ! indicat$ horse-p[] if ! cyl9d]s are #d 94 #d 94 ,i4,h4,p ,pe ,a ,l ,ne_/#cc1jjj #ge #jghed #db 7#d_/ab7 #djjj_/cc1jjj #ge #abef #djjj_/ii1jjj #ch ,! ,indicator ,diagram4--,at ! comm5cem5t ( ?is *apt] we expla9$ t ! "w done by a =ce 0 measur$ by multiply+ ! numb] repres5t+ ! magnitude ( ! =ce 79 p\nds7 by ! di/ance ?r\gh :i* x _h act$ 7measur$ 9 feet74 ,?is product gave u ! quantity ( "w done 9 foot-p\nd units4 ,?us 8quantity ( "w done0 is really ! product ( two numb]s1 j z ! area ( a rectangul> floor space is measur$ by l5g? times bread?4 ,9 symbols we write ,w ,f ,s :]e ,f is ! magnitude ( ! =ce or resi/ance 9 p\nds & ,s ! di/ance ?r\gh :i* x has act$1 9 feet4 ,x is int]e/+ to contemplate ?is symbolical expression ,w ,f ,s toge!r ) ! expression ,area ,l5g? ,bread?1 because x gives u a new idea = measur+ "w4 ,imag9e a diagram ( ! k9d %[n 9 ,fig4 #fh1 9 :i* ! curv$ l9e ,,ab has be5 obta9$ by plott+ values ( ,f & ,s = any imag9>y case4 ,! diagram is suppos$ to repres5t pictorially h[ ! p>ticul> =ce "u consid]ation has v>i$ 9 magnitude z x has trav]s$ a space repres5t$1 to "s scale1 by ! l5g? ,,dc4 ,x is cle>ly se5 t ! =ce has be5 decreas+ 9 an irregul> mann] f "s l>ge value repres5t$ by ! height ,,da to a small value repres5t$ by ! height ,,cb4 ,we n[ proce$ to %[ t ! %ad$ area ,,abcd measures ! total am\nt ( "w done by ?is =ce4 ,illu/ration3 ,,fig4 #fh4--;,,=ce-,,space ,,or ,,"w ,,diagram4 ,consid]+ = a mom5t j ! small /rip efdc ( ! diagram we see t x is easy to f9d a rectangle abcd equal 9 area to x4 ,n[ ! height ( ?is rectangle w be ! av]age value ( ! =ce :ile x trav]s$ ! space cd1 & h5ce ! area ( ! rectangle abcd gives ! "w done by ! =ce 9 pass+ f c to d4 ,simil>ly by divid+ up ! :ole diagram we w\ld obta9 a numb] ( little rectangles ea* equal 9 area to ! magnitude ( ! "w done f po9t to po9t4 ,?us ! :ole area ,,abcd gives ! :ole "w done4 ,to measure ! "w done 9 an eng9e cyl9d] we mu/ use "s =m ( indicator4 ,an indicator is an in/rum5t :i* traces out a diagram on :i* absciss 7or horizontal di/ances7 repres5t displacem5ts ( ! pi/on & ord9ates 7or v]tical di/ances7 repres5t ! pressures act+ on ! pi/on4 ,illu/ration3 ,,fig4 #fi4--,,petrol ,,eng9e ,,indicator ,,diagram4 ,,f\r-,,/roke ,,cycle4 ,ord9>y /eam eng9e indicators ) p5cil motion & pap] drum are n suitable = use ) fa/ runn+ petrol eng9es4 ,! mov+ p>ts ( ^! indicators are too heavy & _! spr+s too sluggi% 9 action to keep correct "t ) ^! high spe$ eng9es4 ,aga91 !re is too mu* friction betwe5 ! p5cil & ! pap] drum1 z well z 9 ! lev] jo9ts4 ,!re=e special indicators h to be us$1 9 :i* ! diagram is trac$ out by a beam ( light reflect$ f a mirror on to a gr\nd glass scre5 or photographic plate4 ,"o corn] ( ! mirror is tilt$ 9 "t ) ! movem5t ( ! eng9e pi/on by means ( a special r$uc+ me*anism1 & ano!r corn] ( ! mirror is tilt$ 9 a direction at "r angles to ! fir/ by means ( a v %ort ?9 rod kept 9 contact ) a metal diaphragm subject$ to ! pressure ( ! gases 9 ! eng9e cyl9d]4 ,a beam ( light is ?r[n on to ! mirror f a lamp1 & aft] reflection traces out ! diagram on ! scre5 or plate4 ,su* an in/rum5t w\ld g5]ally be describ$ z a manograph4 ,an indicator diagram f a f\r-/roke eng9e is %[n 9 ,fig4 #fi4 ,! l9e ,,abc repres5ts ! suction /roke ( ! pi/on dur+ :i* ! pressure ( ! gases 9 ! cyl9d] falls a little bel[ t ( ! atmosph]e4 ,atmosph]ic pressure is %[n by ! height ( ! l9e ,,ll above ! base1 or l9e ( z]o pressure 7p]fect vacuum74 ,! inlet valve c be op5$ at ,b & clos$ at ,d aft] ! crank has turn$ ! bottom dead-c5tre & begun ! compression /roke4 ,! l9e ,,cde repres5ts ! compression /roke ( ! eng9e1 dur+ :i* ! gases are compress$ & _! pressure rises4 ,! height ( ! po9t ,e above ! l9e ,,ll gives ! compression pressure to ! scale ( ! diagram4 ,ignition occurs at ,e1 & results 9 an in/antane\s rise ( pressure to ,f due to ! explosion1 :i* is1 h[ev]1 quickly foll[$ by expansion to ,g4 ,! exhau/ valve op5s at ,g1 ! gases are releas$1 & ! pressure falls /ill fur!r to po9t ,h4 ,! l9e ,,ha repres5ts ! exhau/ /roke ( ! pi/on1 & ! exhau/ valve w\ld be clos$ aft] ! crank _h pass$ its upp] dead-c5tre & comm5c$ ! suction /roke4 ,! di/ance m>k$ 7x7 on ! diagram measures ! cle>ance volume 7or volume ( ! space above ! pi/on conta9+ ! valves & ref]r$ to z ! combu/ion *amb]7 to ! same scale t ! l5g? ( ! diagram measures ! volumetric displacem5t ( ! pi/on4 ,! volume trac$ out by ! pi/on dur+ any work+ /roke is measur$ by multiply+ ! area ( ! pi/on 9 squ>e c5timetres by ! l5g? in*es ( ! /roke 9 c5timetres ! product giv+ u in*es ! capacity ( ! cyl9d] 9 cubic c5timetres4 ,! in*es area ( ! diagram ,,hefg gives ! "w done dur+ "o cycle ( op]ations1 & ! area ( ! small diagram ,,abcd gives ! "w lo/ 9 tak+ 9 & expell+ ! *>ge4 ,! small area %\ld be subtract$ f ! l>ge "o to get ! useful "w done p] cycle ( op]ations4 ,! area ( ! diagram ,,hefg may readily be obta9$ by f9d+ its v]tical height at a numb] ( equidi/ant po9ts1 & f ^! measurem5ts asc]ta9+ ! av]age or mean height ( ! diagram4 ,! av]age height ( ! diagram 79 in*es7 multipli$ by its l5g? 7also 9 in*es7 gives ! area 9 squ>e in*es4 ,illu/ration3 ,,fig4 #gj4--;,,indicator ,,diagram ,,f ,a ,,two-,,/roke ,,eng9e4 ,! av]age or mean height ( ! diagram also gives :at we t]m ! mean effective pressure act+ on ! pi/on1 & con/itutes ! ,pe ( ! indicat$ horse-p[] =mula above4 ,! area ,,abcd is always small & g5]ally neglect$ ) f\r-/roke eng9es4 ,!re are two sep>ate diagrams = a two-/roke eng9e4 ,! diagram = ! work+ cyl9d] is ,a#a;,b#a;,c#a;,d#a 9 ,fig4 #gj1 & t = ! crank*amb] is ,e#a;,f#a;,g#a;,h#a4 ,! effective "w done p] cycle is measur$ by ! diff]5ce 9 ! area ( ^! two diagrams4 ,! pi/on uncov]s ! exhau/ port at ,b#a & closes x aga9 at ,c#a2 x uncov]s ! inlet port at ,f#a & cov]s x aga9 at ,g#a4 ,f ,f#a to ,g#a ! *>ge is be+ deliv]$ f ! crank*amb] to ! work+ cyl9d]4 ,! area ( ! loop ,e#a;,f#a;,g#a;,h#a is l>g] ?an ! correspond+ portion ( ! f\r-/roke diagram & %\ld n be neglect$4 ,,*apt] ,,xii ,,liquid ,,fuels ,important factors 9 ! *oice ( a liquid fuel = use 9 portable int]nal combu/ion eng9es are3 7#a7 l[ co/2 7#b7 ease & safety ( transportation or /orage2 7#c7 high volatility1 i4e41 readily conv]tible into vap\r2 7#d7 non-corrosive action on metals2 7#e7 high heat effici5cy2 7#f7 ability to give satisfactory results 9 exi/+ types ( int]nal combu/ion eng9e4 ,petrol is a liquid fuel compos$ ( c>bon 7,c7 & hydrog5 7,h7 9 *emical comb9ation4 ,! pr9cipal me?od ( produc+ petrol is by di/illation ( crude petroleum4 ,! be/ mixture to use 9 a petrol eng9e is "o compos$ ( #b cubic feet ( petrol vap\r to e #ih cubic feet ( air4 ,petrol does n require any heat to vaporize x "u ord9>y atmosph]ic conditions4 ,pre-ignition ( ! *>ge is liable to occur if ! compression pressure exce$s #ajj lbs4 p] squ>e in*4 ,x does n corrode or det]iorate metal p>ts1 b leaves a black c>bon deposit if n prop]ly burn$4 ,its volatility is high & its specific gravity is l[1 be+ ab\t #jga4 ,an av]age figure = ! calorific value ( petrol w\ld be #bj1jjj ,b4 ,?4 ,u4 p] lb4 ,petrol is v exp5sive & also ne$s c>e 9 h&l+4 ,private motori/s are n all[$ to /ore petrol or b5zol4 ,b5zol is a liquid fuel conta9+ m c>bon 7,c7 & less hydrog5 7,h7 ?an petrol4 ,! pr9cipal me?od ( obta9+ b5zol is by di/illation ( coal t>4 ,! /r5g? ( ! mixture %\ld be su* t a little m air is suppli$ 9 proportion to ! quantity ( fuel us$ ?an is requir$ = petrol4 ,g5]ally1 x may be said t :5 an eng9e has be5 runn+ on petrol & is *ang$ ov] to b5zol ! size ( ! c>burettor jet orifice %\ld be slightly r$uc$ & ! weight ( ! float increas$--no o!r *anges ne$ be made any:]e4 ,b5zol is v volatile & also highly dang]\s to h&le1 on acc\nt ( its l[ fla%-po9t4 ,x (t5 conta9s impurities :i* attack ! metal p>ts ( ! eng9e & gum up ! valves4 ,x is m liable to deposit c>bon ?an petrol4 ,b5zol attacks rubb]1 & pa9t on coa*work4 ,x is z exp5sive z petrol at ! pres5t "t4 ,! specific gravity ( b5zol may be tak5 z #jhh & its calorific value z #ai1jjj ,b4 ,?4 ,u4 p] lb4 ,x may be compress$ above #ajj lbs4 p] squ>e in* )\t pre-ignit+4 ,alcohol is a liquid fuel compos$ ( c>bon 7,c71 hydrog5 7,h71 & oxyg5 7,o74 ,! pr9cipal me?od ( obta9+ alcohol is f ! f]m5tation ( vegetable matt]1 su* z potatoes1 beetroot1 etc4 ,ab\t #f cubic feet ( vaporiz$ alcohol to e #id cubic feet ( air %\ld be us$4 ,! volatility ( alcohol is v poor comp>$ ) petrol or b5zol1 & x g5]ally conta9s "s wat] 9 susp5sion4 ,x w /& d\ble ! compression pressure ( petrol )\t pre-ignit+4 ,alcohol is n s liable to deposit c>bon z petrol or b5zol1 b is v liable to cause ru/4 ,x is n obta9able z a fuel 9 ,great ,brita9 at pres5t1 ow+ to ! high duty on x4 ,eng9es = use ) alcohol ought really to be specially con/ruct$ = ! purpose4 ,its calorific value is only #ab1jjj ,b4 ,?4 ,u4 p] lb41 & its specific gravity is #jhb4 ,alcohol requires to be heat$ be=e x w vaporize1 ?is heat g5]ally be+ obta9$ f ! exhau/ gases aft] ! eng9e has be5 fir/ />t$ up4 ,alcohol is fairly safe to h&le or /ore4 ,p>aff9 is obta9$ dur+ ! di/illation ( petrol f crude petroleum1 & consi/s ( c>bon 7,c7 & hydrog5 7,h7 9 almo/ ! same proportions z petrol4 ,its volatility is l[1 & x requires heat to vaporize x4 ,! heat requir$ = vaporization is usually obta9$ f ! exhau/ gases aft] ! eng9e has be5 got runn+4 ,9 />t+ up a lamp mu/ be us$ = heat+ ! vaporiz] ( ! c>burettor4 ,p>aff9 w /& a little high] compression ?an petrol be=e pre-ignit+4 ,! specific gravity ( p>aff9 may be tak5 z #jhj & its calorific value z #ah1jjj ,b4 ,?4 ,u4 p] lb4 ,x is mu* *eap] ?an ei!r petrol or b5zol1 be+ only ab\t "o-?ird ( ! co/4 ,! *ief objections to its use are its smell & ! greasy "* ( ! /a9 left by x on coa*work or clo!s2 also ! difficulty ( hav+ to heat ! vaporiz+ *amb] ( ! c>burettor4 ,x is mu* saf] to h&le & /ore ?an ei!r petrol or b5zol1 & requires ab\t ! same proportion ( air to =m an explosive mixture z t giv5 = petrol4 ,! range ( v>iation ( /r5g? 9 ! mixture :i* is p]missible ) p>aff9 is mu* less ?an ) ei!r petrol1 b5zol1 or alcohol4 ,alcohol has ! greate/ range ( v>iation 9 mixture /r5g?4 ,p>aff9 is also v liable to deposit c>bon1 ow+ to ! small range ( v>iation p]missible 9 ! /r5g? ( ! mixture4 ,!rmal ,effici5cy4--,9 ! =ego+ notes we h us$ c]ta9 t]ms :i* h n previ\sly be5 expla9$1 & !re=e x is necess>y to give "o or two def9itions4 ,! ,specific ,gravity ( a fuel is ! ratio ( ! weight ( "o gallon ( ! fuel to ! weight ( "o gallon ( wat]4 ,z a gallon ( wat] weighs #aj lbs41 x w be evid5t f ! above notes t a gallon ( petrol only weighs #ga lbs41 :]eas a gallon ( b5zol w weigh #hh lbs4 7approx471 h5ce x is n surpris+ to le>n t m mileage p] gallon is obta9$ ) b5zol ?an ) petrol1 ev5 ?\gh ! calorific value ( b5zol1 p] lb41 is less ?an t ( petrol4 ,sometimes ! specific gravity is ref]r$ to z ! d5sity ( ! fuel1 b ?is is only correct :5 grammes & c5timetres are be+ us$4 ,! d5sity ( any fuel is ! weight ( #a cubic foot express$ 9 p\nds or1 9 g5]al t]ms1 ! mass ( unit volume ( ! fuel4 ,! d5sity ( petrol 9 ,engli% units w\ld be ab\t #dd lbs4 p] cubic foot4 ,"o ,briti% ,!rmal ,unit is ! quantity ( heat requir$ to raise ! temp]ature ( #a lb4 ( wat] by #a degree 7,fahr5heit scale7 :5 ! temp]ature ( ! wat] is ab\t #fj;,f4 ,! ,calorific ,value ( any fuel 7reckon$ on ! ,briti% sy/em ( units7 is ! am\nt ( heat 7express$ 9 ,briti% ,!rmal ,units7 :i* w be giv5 out by #a lb4 ( ! fuel :5 x is completely burn$4 ,! liquid fuels we h to deal ) are hydroc>bon comp\nds1 & :5 completely burn$ ! :ole ( ! c>bon is burn$ to c>bon dioxide 7,,co#b7 & ! hydrog5 to /eam 7,h#b,o71 leav+ no residue4 ,by means ( a calorimet] we c exp]im5tally det]m9e ! calorific value ( any fuel4 ,x has long be5 kn[n t "w c be turn$ into heat1 & ! petrol eng9e is a good example ( ! rev]se process :i* consi/s 9 turn+ heat into "w4 ,9 a /eam eng9e & boil] plant ! heat ( ! fuel is lib]at$ "u ! boil]1 & !n a portion ( x gets transf]r$ to ! wat] 9 ! boil] & =ms /eam1 :i* is !n tak5 to ! eng9e & does "w 9 ! cyl9d]1 ! :ole be+ a wa/eful process4 ,! petrol eng9e is an int]nal combu/ion eng9e1 or "o 9 :i* ! fuel is burnt inside ! eng9e cyl9d] itself & conv]t$ directly into "w4 ,f e ,briti% ,!rmal ,unit ( heat lib]at$ by ! combu/ion ( ! fuel 9 ! cyl9d] we %\ld be able to get #ggh foot-p\nds ( "w if ! !rmal 7or heat7 effici5cy ( ! eng9e 0 #ajj p] c5t4 ,! !rmal effici5cy 77 ( any eng9e may be def9$ z ! ratio :i* ! heat equival5t ( ! "w done p] m9ute by ! eng9e be>s to ! heat :i* w\ld be lib]at$ by ! complete combu/ion ( ! quantity ( fuel admitt$ to ! cyl9d] p] m9ute4 ,?us-- 7,horse-p[] ( ! ,eng9e #cc1jjj7_/ggh ---------------------------------------- ---------------------------------------- -------------------------------------- 7,numb] ( p\nds ( fuel consum$ p] m9ute7 7,calorific ,value ( ! fuel7 ,example3--,an eng9e develop+ #cj horse-p[] uses #jej lb4 ( b5zol p] m9ute4 ,:at is its !rmal effici5cy8 ,! calorific value ( b5zol may be tak5 z #ai1jjj ,b4 ,?4 ,u4 p] lb4 7#cj #cc1jjj_/ggh7_/7jej #ai1jjj7 #jacd1 or #acd p] c5t4 ,,app5dix ,,eng9e ,,tr\bles ,_m ( ! tr\bles t are likely to arise h already be5 ref]r$ to 9 previ\s *apt]s1 b ! foll[+ additional notes may be f\nd useful4 #a4 ,eng9e refuses to />t4 ,c>e mu/ be tak5 to obs]ve exactly :at happ5s1 & "o _c d bett] ?an ask oneself m5tally "s ( ! foll[+ que/ions4 7a7 ,is ! ignition 8on08 ,if a magneto is fitt$ ! e>? connexion %\ld be op51 b if a coil & accumulator are fitt$ ! e>? connexion %\ld be clos$4 7b7 ,is ! petrol rea*+ ! c>burettor jet8 ,be=e remov+ ! jet = ! purpose ( exam9+ & clean+ x1 x w\ld be advisable to asc]ta9 :e!r ! petrol 0 rea*+ ! float *amb]4 ,provid$ !re is a reasonable am\nt ( petrol 9 ! tank & ! tap is turn$ on1 !re mu/ be a /oppage ei!r 9 ! petrol filt]1 ! petrol pipe1 or ! bottom portion ( ! float *amb]4 ,exam9e ! filt] & float *amb] be=e disconnect+ any pipes4 7c7 ,is !re a good compression 9 all ! cyl9d]s8 ,if !re does n appe> to be any compression 9 any ( ! cyl9d]s1 x is probable t ! c>burettor ?rottle is clos$ & no air or gas c ent] ! cyl9d]s4 ,if !re is a good compression 9 "s cyl9d]s & a poor "o or none at all 9 o!rs !n-- 7#a7 ,"o or m ( ! valves may be held (f its seat by dirt1 by di/ortion1 or by "s d]angem5t ( ! valve ge>4 ,exam9e ! valve ge> ext]nally1 turn+ ! eng9e sl[ly to wat* its action4 ,aft]w>ds remove valve caps & inspect valves if necess>y4 7#b7 ,"o or m ( ! sp>k+ plugs or valve caps may be %ort ( its wa%]4 ,9 ?is case ! bl[ w be he>d z ! eng9e is turn$ r\nd by h&4 7#c7 ,a pi/on may be crack$ or brok5 or a cyl9d] crack$4 7#d7 ,a cyl9d] may h got badly worn & ! r+s on ! pi/on jamm$ s t !y no long] keep x gas-tight4 7d7 ,is ! eng9e v /iff to turn ov]8 ,/iffness is due z a rule to lack ( oil on ! cyl9d] walls1 caus$ by abs5ce ( oil 9 crank*amb] or ! film ( oil on ! cyl9d] walls hav+ be5 wa%$ (f :5 prim+ ! eng9e ) petrol 9 attempt+ to />t x4 ,if a connect+ rod is b5t1 or ! crank%aft di/ort$ or a pi/on r+ brok51 /iffness w also be not$4 ,v (t5 by remov+ ! valve caps & p\r+ a teaspoonful ( oil or p>aff9 into ea* cyl9d] ! eng9e may be fre$ by vigor\sly turn+ ! />t+ h&le by h& until ! cyl9d]s & pi/ons are well lubricat$4 7e7 ,is !re any sign ( an attempt to fire ! *>ge su* z an occasional puff ( smoke f ! exhau/ or inlet1 or an occasional j]k r\nd ( ! eng9e z y turn ! />t+ h&le1 or an occasional 8bang0 9 ! exhau/ box8 ,if ! ignition is 8on0 & ! c>burettor jet cle>1 ! compression good & ! eng9e q free1 yet !re is no sign ( a 8fire0 f any ( ! cyl9d]s1 x is possible t air is leak+ into ! induction pipe ?r\gh a faulty jo9t or any "o ( ! foll[+ ignition tr\bles may h occurr$3-- 7f7 ,defective sp>k+ plug or plugs4 ,?is may arise f wat] or oil or dirt betwe5 ! plug po9ts2 or f faulty insulation 9 ! body ( ! plug4 ,to te/ :e!r ! plugs are at fault an easy me?od is to take a screwdriv] ) a wood5 h&le & place ! metal blade on ! t]m9al ( ! plug1 lett+ ! po9t come ab\t "o ?irty-second ( an in* f ! metal ( ! cyl9d] or any ( ! pipes2 :5 ! eng9e is turn$ by h& ! sp>k w be se5 to pass across ?is improvis$ gap if ! magneto & leads are 9 ord]4 7g7 ,defective electrical connexions4 ,! high t5sion cables may be brok51 or disconnect$1 or %ort-circuit$4 ,! e>? wire may be %ort-circuit$ 7i4e41 9 electrical contact ) "s o!r wire or metal fitt+74 ,!re may be a %ort-circuit 9 ! ignition swit*4 7h7 ,defective magneto or coil4 ,! l[ t5sion contact break] lev] may be jamm$ s t ! make & break is inop]ative1 or "o ( ! c>bon bru%es may h got brok54 ,occasionally "o f9ds ! magnets ( ! ma*9e h lo/ _! p[]2 or !re is "s electrical defect 9 ! armature or cond5s]4 ,! batt]y may h become exhau/$4 ,! trembl] blade may be /uck up4 ,wat] may h f\nd its way on to ! high t5sion electrode or into ! safety sp>k gap4 #b4 ,eng9e />ts up fairly well1 runs a little1 & !n /ops4 ,take c>e to notice ! mann] 9 :i* ! eng9e runs & /ops4 ,note :e!r x runs regul>ly or irregul>ly & = h[ long a "t4 ,if ! eng9e runs regul>ly ) all cyl9d]s fir+1 !n probably ! exhau/ is *ok$ or ! petrol supply fails4 ,failure ( ! petrol supply may be due to ! use ( too small a jet 9 ! c>burettor1 too l[ a level 9 ! float *amb]1 or to p>tial /oppage 9 ! pipe l9e4 ,ano!r cause ( ?is tr\ble ( int]mitt5t runn+ w\ld sometimes be loss ( batt]y p[] :5 us+ coil ignition1 i4e41 batt]ies want re*>g+4 ,if ! eng9e runs irregul>ly ! tr\ble is probably due to too mu* oil 9 ! cyl9d]s caus+ ! plugs to misfire1 ! pres5ce ( wat] or dirt 9 ! petrol1 a defective valve1 a brok5 c>bon bru%1 or poor electrical contact some:]e 9 ! magneto1 ! l[ t5sion contact break] 7coil71 or high t5sion di/ributor 7coil74 ,to asc]ta9 :e!r ! eng9e is fir+ regul>ly on all cyl9d]s1 or to detect :i* cyl9d] is misfir+1 ! be/ proc$ure is to op5 ! compression taps 9 turn :ile ! eng9e is runn+ & 9 ea* case spe$ up ! eng9e :ile y h ! tap op54 ,cyl9d]s :i* are fir+ well give a %>p crack+ noise1 ^? :i* are n fir+ m]ely give a hiss+ noise4 ,if no compression taps are provid$1 ea* plug mu/ be %ort-circuit$ to ! frame 9 turn by ! screwdriv] me?od giv5 above4 ,! %ort-circuit+ process causes a r$uction 9 eng9e spe$ except on t plug :i* is already n fir+4 ,! me?od is n s good z ! compression tap process1 because ! plugs (t5 get oil$ up dur+ ! %ort-circuit+ process & ! difficulty is acc5tuat$4 #c4 ,tim+ ! ,ignition4 ,my colleague1 ,mr4 ,oliv] ,mit*ell1 has po9t$ out to me t x is (t5 impossible to tell directly :5 ! pi/on is exactly at ! top ( its /roke1 & he recomm5ds a /udy ( ! accompany+ ,valve ,sett+ ,diagram 7,figure #ga74 ,f ?is x w be se5 t x is suffici5tly ne> to br+ ! eng9e fir/ ( all to su* a position t ! exhau/ valve has j clos$2 !n make a *alk m>k on ! fly:eel & give ! eng9e "o complete turn r\nd2 ! pi/on w !n be 9 ! fir+ position if ! fly:eel is turn$ a %ade backw>ds4 ,ano!r me?od w\ld be to ret>d ! ignition fully & "t x s t ! sp>k occurr$ "o complete revolution aft] ! inlet valve _h j comm5c$ to op54 ,:5 ei!r valve is clos$ its tappet c be felt to be free1 ! am\nt ( fre$om dep5d+ ^u ! cle>ance betwe5 ! tappet head & valve /em4 ,illu/ration3 ,,fig4 #ga4--;,,diagram ,,( ,,valve ,,sett+4 ,,index ,a ,accel]ation1 quick1 #gh -- "u load1 #ib ,accessibility1 #ci1 #ej ,accumulator1 #fa ,adapt]1 #ib ,adju/able tappet head1 #bi1 #cj ,adju/+ screws1 #ai ,advanc$ ignition1 #ee1 #ef1 #ei ,a]oplane eng9e cyl9d]1 #aj1 #af ,air1 #a1 #da1 #db1 #df1 #hg1 #hi1 #aad -- c>burett$1 #db1 #ig -- lock1 #gb -- pump1 #ej -- -- h&1 #ej -- scav5g+1 #af1 #ce1 #hd1 #he1 #hg1 #hh1 #hi -- to petrol ratio1 #db -- valve1 automatic extra1 #dc1 #di -- velocity1 #df1 #gj -- volume (1 relative to petrol vap\r1 #db1 #ajh -- weight (1 relative to petrol vap\r1 #db ,alcohol1 prop]ties (1 #aji ,anti-freez+ solution1 #gb ,armature ( magneto1 #eb1 #ed -- relative spe$s ( eng9e & magneto1 #ed1 #ee ,atmosph]ic pressure1 #c1 #ij ,atomization ( petrol1 #dh1 #di ,automatic extra-air valve1 #dc1 #di -- inlet valve1 #hb1 #hd1 #hh ,b ,backfire1 #fb1 #hd ,balance1 p]fect1 #gf -- want (1 #ge1 #gf -- weight1 #be ,balanc+ ! crank%aft1 #be1 #bf1 #gf ,b>rel ( cyl9d]1 #ab ,base1 oil1 #h1 #dj1 #fe ,batt]y1 #aaf ,be>+s1 ma91 #bd1 #fd ,b5zol1 prop]ties (1 #de1 #ajh ,blade1 trembl]1 #eg ,boil+ ( wat] 9 jackets1 #gb ,boxes1 core1 #aa ,brake1 = petrol eng9e1 #ajj ,brake horse-p[]1 #ii ,briti% !rmal unit1 #aaa ,bru%1 c>bon1 #ec1 #ee1 #aaf ,built-up cyl9d]1 #af -- fly:eel1 #bg ,buoyancy1 #de ,burn+1 rate (1 ( mixture1 #a1 #eg -- ( deflector1 #ia ,bur/+ ( fly:eel rim1 #bg ,bu%1 phosphor bronze1 #bc ,c ,cables1 high t5sion1 #fa ,calorific values1 #aaa ,cam1 #cj1 #cc ,cam%afts1 #bi1 #cc1 #dj ,cams1 /ation>y1 = magneto1 #ec ,capacity ( cyl9d]1 #ajf ,caps1 valve1 #ac1 #ca ,c>bon bru%1 #ec1 #ee1 #aaf -- deposit1 #fc1 #gh ,c>buration1 #db1 #id ,c>burett$ air1 #db1 #ig ,c>burettor1 #e1 #h1 #db1 #hb -- jet type1 #db -- multiple jet1 #dg1 #id -- po9ts ( a good1 #di -- rec5t improvem5ts 91 #dg -- spray type1 #db -- surface type1 #db -- wick type1 #db ,ca/+s1 cyl9d]1 #aa ,ca/-9-pairs1 cyl9d]s1 #af ,c5trifugal =ce1 #bg ,*a9drive1 sil5t1 #ch ,*>ge1 #c1 #hj ,*>g+ pump1 #hj ,*assis1 #dj1 #ga ,*oke tube1 #df1 #dg ,*rome /eel1 #bj1 #cf ,circulat+ wat] pump1 #h1 #ga ,circulation1 =c$1 #ga -- local1 #gc -- pump1 #ga -- !rmo-syphon1 #fi ,cle>ance betwe5 pi/on & cyl9d] walls1 #ag -- ( valve tappet1 #bi -- space1 #d1 #aje1 #ajg ,coil ignition1 #eg1 #ei1 #fa -- -- sy/em1 wir+ diagram =1 #fa -- non-trembl]1 #ei -- supplem5t>y1 = />t+1 #eh -- trembl] patt]n1 #eg1 #fa ,collector r+1 #ee ,combu/ion1 #gh -- *amb]1 #d1 #if ,comp5sat+ jet1 #dh ,compression1 mean+ (1 #c -- pressure1 #hb1 #hc1 #aje -- /roke1 #f1 #hj ,cone clut*1 #bg ,connect+ rod1 #d1 #ba1 #if -- -- =ces act+ on1 #bj -- -- phosphor bronze1 #bj1 #bb -- -- /eel1 #bc ,consumption ( fuel1 #gi -- ( oil1 #fg ,contact break]1 l[ t5sion1 #ec -- -- wipe =m (1 #eh -- screws1 plat9um tipp$1 #ec1 #eg ,cool+1 #fi ,core-boxes1 #aa ,core1 iron1 ( ignition coil1 #eg ,co/ ( production1 #bb1 #fd1 #gi ,cott]1 #bi ,crank *amb]1 #h1 #ci -- -- gas-tight1 #ha1 #hb1 #if -- *eeks or webs1 #bd -- motor-cycle1 #bc -- p91 #bd -- radius1 #d -- %aft1 #bc1 #bh1 #gg1 #hi ,crank %aft1 balanc+ !1 #be1 #gf -- -- vibration (1 #gf -- -- :ipp+ (1 #gf ,cu%ion ( hot gas1 #ic1 #if ,cut-out1 #ij ,cycle1 f\r-/roke1 #e -- motor1 #aj1 #aa -- ,otto1 #e -- two-/roke1 #hj ,cyl9d]1 #e1 #i -- a]oplane eng9e1 #ae1 #af -- air-cool$1 #aa1 #ae -- b>rel1 #ab -- built-up1 #af -- ca/+s1 #aa -- head1 deta*able1 #cb1 #gh -- jackets1 #ab1 #ae1 #fi -- ,l-head$1 #af -- pump1 #hg1 #hh1 #ajg -- revolv+1 #aj -- ,t-head$1 #ae -- wat]-cool$1 #h1 #cb1 #hb1 #if -- work+1 #ha1 #hg1 #ajg ,cyl9d]s1 ca/ en bloc1 #af1 #gg -- ca/ 9 pairs1 #af -- ca/ sep>ately1 #af -- *oos+ ! numb] (1 #ge -- fir+ ord] (1 #fj ,d ,dead c5tre1 #d1 #aaf -- gases1 #hc ,defective coil1 #aad1 #aaf -- ignition sy/em1 #aad -- magneto1 #aad1 #aaf -- sp>k+ plug1 #aac1 #aad -- valve1 #aac1 #aad1 #aaf ,deflector1 #ha1 #hg1 #ic1 #if -- ov]heat+ (1 #hd1 #ia ,d5sity1 #de1 #aaa ,deposit ( c>bon1 #fc1 #gh ,description ( a typical petrol eng9e1 #h ,deta*able cyl9d] head1 #cb1 #gh ,devices1 ignition1 #ea ,diagram1 indicator1 #ib1 #ajb -- = f\r-/roke eng9e1 #aje -- = two-/roke eng9e1 #ajf -- = valve sett+1 #aaf -- "w1 #ajc ,difficulties 9 />t+1 #gb1 #ge1 #ib1 #if1 #aac ,dis*>ge1 sp>k1 #ea1 #ed1 #eh ,di/ributor1 high t5sion1 #eb1 #ec1 #eh ,d\ble sleeve eng9e1 #cb1 #gh ,d[n /roke1 #d1 #ha1 #hb ,draw+s1 work+1 #aa1 #ic ,drip fe$1 #fd1 #ij1 #ib ,drive1 sil5t *a91 #ch ,dual ignition1 #eh -- spr+s1 #ij ,ducts = oil1 #da ,duplex pi/on1 #hf ,durability1 #di1 #gi ,e ,e>?+ wire1 #fj ,ecc5tric1 #cc1 #cf -- rod1 #cc1 #cf -- %eaves1 #cc1 #cf -- /raps1 #cc1 #cf ,economy & durability1 #gi ,effici5cy1 !rmal1 #aaj1 #aaa -- volumetric1 #hc1 #hf1 #hh ,electric sp>k1 #ea1 #ed1 #eh ,electrodes ( sp>k+ plug1 #ea1 #ia1 #ib ,eng9e1 f\r cyl9d]1 #i1 #gf1 #gg1 #id -- int]nal combu/ion1 #aaa -- motor c>1 #i -- multi-cyl9d]1 #gg -- po9ts ( a good1 #ge -- s+le cyl9d]1 #ge -- six cyl9d]1 #gf1 #gg -- tr\bles1 #aac -- two cyl9d]1 #gf -- two-/roke1 #hj1 #ie ,evaporation1 #a ,exhau/ pipe1 #f -- ports1 #ha1 #hh -- -- op51 #ha1 #hh1 #if -- smoky1 #ff -- /roke1 #g1 #ce -- sy/em1 ov]heat+ ( !1 #eg -- valves1 #e1 #aj1 #cg1 #ha -- valves1 tim+ ( !1 #ce1 #cg1 #gh1 #aaf ,explosion /roke1 #g1 #ba1 #bf1 #ce ,explosive mixtures1 #a1 #ajh1 #aji1 #aaj ,extra-air valve1 #dc1 #di1 #id ,f ,fan1 #gj -- pulley1 #h1 #gj ,fe$1 drip1 #fd1 #ij1 #ib ,fibre1 tappet head1 #cj -- :eel1 #ch ,film ( oil1 #fe ,filt]1 petrol1 #dc ,f9s1 heat radiat+1 #gj ,fir+ ord] ( ! cyl9d]s1 #fj -- /roke1 #fj ,fix$ ignition1 #eg ,flanges1 #ab1 #ac ,fla% po9t ( lubricat+ oils1 #fc1 #fg1 #fh ,fla%+ back f exhau/1 #hd1 #ib1 #ic1 #ie ,flexibility1 #gg1 #hc1 #ib ,float *amb]1 #dc1 #dd1 #id ,flood+1 #de1 #id ,fluctuation ( eng9e spe$1 #bg ,fly:eel1 #h1 #bf -- built-up1 #bg -- function (1 #bf -- rim1 bur/+ (1 #bg -- s+le /amp+ ( /eel1 #bh ,=ce1 #ih -- c5trifugal1 #bg ,=c$ circulation1 #ga -- lubrication1 #fe1 #ij ,=ces1 in]tia1 #ge -- space diagram1 #ajc ,f\r cyl9d] eng9e1 #i1 #gf1 #gg1 #id -- /roke cycle1 #e ,frequ5cy ( vibrations1 #gf ,fuel1 consumption (1 #gi ,fuels1 liquid1 #ajh ,furr+ ( tubes & jacket spaces1 #gc ,g ,gap ( sp>k+ plug1 #ea1 #ed ,gas1 compress+ !1 #c -- pump1 #hj -- tight crank*amb]1 #ha1 #hb1 #if ,ge>+1 ov]head1 #af ,ge>s1 helical1 #ch --spur1 #cg1 #ch ,g5]al ov]heat+1 #gb1 #gc --pr9ciples1 #a ,gill$ tube1 #gj1 #gd ,gills1 #gj ,gravity fe$1 #ej ,grease 9 cyl9d] jackets1 #gb ,gr9d+ 9 a valve1 #ca ,gudgeon p91 #ag1 #ah -- -- we> on1 #ai1 #ij ,guides1 valve /em1 #h1 #ab1 #ac1 #cj ,h ,h& air pump1 #ej ,h&le1 />t+1 #ga ,head1 adju/able tappet1 #cj -- ( wat]1 #fi1 #ga ,heat effici5cy1 #aab -- en]gy ( ! petrol mixture1 #i1 #ag1 #aaa -- radiat+ f9s1 #aa1 #gj -- surplus1 #i1 #ag ,helical tee?1 #ch ,high t5sion cables1 #fa -- -- di/ributor1 #eb1 #ed1 #eh -- -- magneto1 #h1 #ea1 #eb1 #ed1 #hi -- -- t]m9als1 #ea1 #eg ,holes1 cott]1 #bi -- oil1 #fc ,honeycomb radiator1 #gj1 #gd ,horse-p[]1 #ih -- brake1 #ii -- indicat$1 #aja -- ,jo9t ,committee's =mula1 #aja -- ( c>1 #ii -- ,treasury =mula1 #aja ,hot-wat] jacket1 #dc1 #dg1 #id ,hydrog51 #ajh1 #aji ,i ,idle /roke1 #bf1 #hb ,ignition1 advanc$1 #ee1 #ef1 #ei -- coil1 #eg1 #ei1 #fa -- devices1 #ea -- dual1 #eh -- fix$1 #eg -- knock1 #eg1 #hd -- normal1 #ee -- ret>d$1 #ee1 #ei1 #fb -- syn*roniz$1 #ei1 #fa -- tim+ !1 #fj1 #fb1 #aaf -- two-po9t1 #ei ,improv$ sy/em ( spla% lubrication1 #fd ,improvem5ts 9 c>burettors1 rec5t1 #dg ,indicat$ horse-p[]1 #aja ,indicator diagram1 #ib1 #ajb -- -- = f\r-/roke eng9e1 #aje -- -- = two-/roke eng9e1 #ajf ,indicator1 optical1 #ib ,induction pipe1 #e1 #h1 #dc1 #hb ,in]tia =ces1 #ge ,inflammable vap\r1 #fc ,injection ( wat] to cyl9d]1 #ib ,inlet ports1 #ha1 #hh -- valve1 air1 automatic1 #dc1 #di1 #hh -- -- automatic1 = gase\s mixture1 #hb1 #hh -- -- me*anically op]at$1 #e1 #cj1 #ca -- -- tim+ !1 #cd1 #cg1 #gh1 #aaf -- wat] pipe1 #h1 #gj1 #gc ,inspection op5+s1 #ci ,insulators1 #ea ,int]nal wat] cool+1 #ib ,j ,jacket1 cyl9d]1 #ab1 #ae1 #fi -- hot wat]1 #dc1 #dg1 #id -- space1 too l>ge1 #gc -- wat]1 ov]heat+ (1 #gb -- -- temp]ature (1 #gd -- -- weight (1 #gd1 #hi ,jet1 atomiz+1 #dh -- comp5sat+1 #dh -- petrol1 #dd1 #df ,jet-9-tube c>burettor1 #db ,jigs1 #bd ,jockey pulley1 #ch ,jo9ts1 wat]-tight1 #aa1 #ae ,j\rnals1 #bd ,k ,kean's two-/roke eng9e1 #he1 #id ,knock ignition1 #eg1 #gc1 #hd ,knock+1 accel]ation1 #ib1 #ic1 #ie -- int]mitt5t1 #hd1 #ib1 #ic -- spasmodic1 #hd1 #ia ,l ,l-head$ cyl9d]s1 #af ,lag 9 op5+ & clos+ valves1 #cd -- "t1 #ef ,lead ( valve1 #ce ,leakage ( gas pa/ ! pi/on1 #ah1 #aad ,leaky pi/ons1 #aad ,liquid fuels1 #ajh -- petrol1 #ajh ,local circulation1 #gc -- ov]heat+1 #gb ,lock1 air1 #gb ,lock nuts1 #bi ,l[ t5sion contact break]1 #eb -- -- t]m9al1 #eg1 #eh -- torque1 #ge ,lubrication1 =c$1 #fe1 #ij -- improv$ sy/em ( spla%1 #fd -- spla% sy/em (1 #fc ,m ,magneto armature1 relative spe$s (1 #ed1 #ee1 #id -- = f\r cyl9d] eng9e1 #eb1 #ed1 #fj -- = six cyl9d] eng9e1 #ed -- high t5sion1 #h1 #ci1 #dj -- ignition sy/em1 wir+ diagram =1 #fj -- rac+ patt]n1 #id -- two-/roke eng9e1 #id ,make & break1 #ec1 #eh1 #fb ,manograph1 #ajd ,mat]ials1 pack+1 #ae ,mean effective pressure1 #hi1 #ajg ,me*anically op]at$ valve1 #cj1 #hd ,metal segm5ts ( di/ributor1 #ee ,mild /eel1 #bc ,mileage p] gallon1 #aaj ,misfir+1 #hd1 #aaf ,mix+ *amb]1 #dc1 #dg ,mixture1 explosive1 #a1 #ajh1 #aji1 #aaj -- heat en]gy ( !1 #i1 #ag1 #aaa -- /r5g? ( ! #a1 #db1 #ajh1 #aji1 #aaj -- too weak a1 #df -- weak5+ !1 #di1 #gc ,mom5tum1 #ce1 #cf ,monobloc ca/+1 #gg ,motor c> eng9e1 #i -- cycle1 #aj1 #aa -- -- crank1 #bc ,m\lds1 #aa ,multiple jet c>burettor1 #dg1 #id ,mu%room type valves1 #e1 #h1 #cj ,n ,natural circulation1 #fi ,ne$le valve1 #dd ,nickel /eel1 #bj1 #cf ,noise f valves1 #cj1 #ci ,non-trembl] coil1 #ei ,normal ignition1 #ee ,o ,oil base1 #h1 #dj1 #fe -- consumption (1 #fg -- ducts1 #da -- film1 #fe -- holes1 #fc -- pressure1 #fe1 #fg -- price (1 #fg -- prop]ties (1 #fc -- pump1 #h1 #ci1 #dj1 #fe1 #fg -- -- spe$ (1 #fg -- tr\ghs1 #fe ,op5 exhau/ port1 #ha1 #hh1 #if ,optical indicator1 #ib ,orifice1 #de1 #gc ,oscillations1 torsional1 ( ! crank%aft1 #gg ,otto cycle1 #e ,outlet wat] pipe1 #h1 #gj1 #ga1 #gc ,ov]fl[ pipe1 #gb ,ov]head ge>+1 #af ,ov]heat+ ( deflector1 #hd1 #ia -- ( ! exhau/ sy/em1 #eg -- g5]al1 #gb1 #gc -- local1 #gb ,ov]load+ ! eng9e1 #ee1 #hi ,p ,pack+ mat]ials1 #ae -- r+s1 #ag1 #ah1 #ha1 #hg1 #ig ,p>aff91 prop]ties (1 #aji ,p>tial seizure1 #ai1 #cc1 #fc1 #fd1 #ij -- vacuum1 #f1 #df1 #hb1 #ij ,passages1 valve1 #aj ,patt]ns1 #aa ,p]fect balance1 #gf1 #gg -- combu/ion1 #gh ,p]iodicity1 #gf1 #gg ,petrol1 consumption (1 #gi -- eng9e1 description ( a typical1 #h -- filt]1 #dc -- jet1 #dd1 #df -- mixture1 heat en]gy (1 #i1 #ag1 #aaa -- pipe1 #dc -- prop]ties (1 #ajh -- supply1 failure (1 #aac -- tank1 #dc -- tap1 #dc -- vap\r1 #a1 #db1 #dc1 #hj -- -- ratio ( air to1 #db ,phosphor bronze bu%1 #bc -- -- connect+ rod1 #bb ,p9k+1 #gi ,pipe1 exhau/1 #f1 #h -- induction1 #e1 #h1 #dc1 #hb -- inlet wat]1 #h1 #gj1 #ga1 #gc -- outlet wat]1 #h1 #gj1 #ga1 #gc -- ov]fl[1 #gb -- transf]1 #hf1 #hg -- v5t1 #ci ,pi/on1 #d1 #ag1 #cb1 #hb1 #if -- duplex1 #hf -- leaky1 #gc1 #aad -- r+1 ca/-iron1 #ah1 #hb -- -- /eel1 #ai -- seizure ( !1 #ai1 #cc -- /eel1 #ai -- weight (1 #ai ,pit* ( ! tee? on a ge> :eel1 #ch ,pla9 tube radiator1 #gd ,plat9um tipp$ contact screws1 #ec1 #eg ,plug1 sp>k+1 #e1 #h1 #ea1 #ia1 #ib ,po9ts ( a good c>burettor1 #di -- -- good eng9e1 #ge ,poppet valve1 #bi1 #gg1 #gi ,ports1 exhau/1 #cc1 #gh1 #ha1 #hh -- inlet1 #cc1 #gh1 #ha1 #hh -- op5 exhau/1 #ha1 #hh1 #if ,p[]1 #ih -- /roke1 #g1 #fj1 #hj ,pre-ignition1 #hd1 #ij1 #ib1 #ie1 #ajh1 #aji1 #aaj ,pressure1 atmosph]ic1 #c1 #ij -- compression1 #c1 #hj1 #hb1 #hc1 #hh1 #aje -- fe$1 #ej -- mean-effective1 #hi1 #ajg -- ( oil1 #fe1 #fg ,prices ( oils1 #fg ,prim>y w9d+1 #ec1 #eh ,production1 co/ (1 #bb1 #fd1 #gi ,prop]ties ( fuels1 #ajh1 #aji1 #aaj -- ( oils1 #fc ,pulley1 fan1 #h1 #gj -- jockey1 #ch ,pump1 air1 #ej -- *>g+1 #hj -- circulat+1 #h1 #fg1 #ga -- cyl9d]1 #hg1 #hh1 #ajg -- gas1 #hj -- h& air1 #ej -- oil1 #h1 #ci1 #dj1 #fe1 #fg -- pi/on1 #hf -- wat]1 #h1 #ci1 #ga ,pu% rod1 #bi ,q ,quick accel]ation1 #gh1 #ib -- make & break1 #ec1 #ei1 #fb ,r ,rac+ patt]n magneto1 #id ,radiator1 gill$ tube1 #fi -- honeycomb1 #gj1 #gd -- size (1 #ga1 #gb1 #gd1 #hi ,rate ( burn+1 #a1 #eg ,rat$ horse-p[]1 #aja ,ratio ( air to petrol vap\r1 #db ,rec5t improvem5ts 9 c>burettors1 #dg ,relative spe$s ( eng9e & magneto1 #ed1 #id ,release ( gases1 #aje ,relief valves1 #fg ,residue1 #fc ,ret>d$ ignition1 #ee1 #eg1 #ei1 #fb ,revolv+ cyl9d]s1 #aj ,r+1 pack+1 #ag1 #ah1 #ha1 #hg1 #ig -- /eel pi/on1 #ai ,roll]1 #bi1 #eh ,rot>y valves1 #gi ,s ,sagg+ ( cam%aft1 #cf ,scav5g+1 #af1 #ce1 #hd1 #he1 #hg1 #hh1hi1 #ic ,scoops1 #fe ,screws1 adju/+1 = gudgeon p91 #ah -- plat9um tipp$1 = contact break]1 #ec1 #eg ,seat ( valve1 #ac1 #bi ,segm5ts1 metal1 ( di/ributor1 #ee ,seizure ( pi/on1 #ai1 #cc1 #fc1 #fd1 #ij ,%afts1 ecc5tric1 #cc ,%eaves1 ecc5tric1 #cc ,%ort-circuit+ t]m9al1 #ee ,sil5ce 9 runn+1 #gi1 #ib1 #ie ,sil5c]1 #f1 #hi ,sil5t *a9 drive1 #ch ,simple two-/roke eng9e1 #ha1 #he ,s+le cyl9d] eng9e1 #ge1 #gf -- sleeve valve eng9e1 #cb -- ?r[ crank%aft1 #bc ,six cyl9d] eng9e1 #gf -- -- -- magneto =1 #ed ,sleeve valves1 #cb1 #gg1 #gh ,sleeves1 d\ble1 #cb1 #gh ,slots1 #cb ,smoky exhau/1 #ff ,sp>k1 electric1 #ea1 #ed1 #eh ,sp>k+ plug1 #e1 #h1 #ac1 #ea1 #ia1 #ib ,spasmodic knock+1 #hd1 #ia ,specific gravity ( fuels1 #ajh1 #aji1 #aaj ,spe$1 fluctuation ( eng9e1 #bg -- ( oil pump1 #fg ,spe$s ( magneto armature & di/ributor1 #ed1 #ee1 #id ,spla% sy/em ( lubrication1 #fc -- -- -- improv$1 #fd ,split p91 #ai ,spray type ( c>burettor1 #db ,spr+s1 dual1 = automatic valve1 #ij -- valve1 #h1 #bi1 #ij ,sprocket :eels1 #ch ,spur ge>s1 #ch ,/amp+s = connect+ rods1 #bb ,/>t+ difficulties1 #gb1 #ge1 #ib1 #if -- h&le1 #h1 #ga ,/ation>y cams = magneto1 #ec ,/eel1 *rome nickel & *rome vanadium1 #bj1 #cf -- fly:eel1 built-up1 #bg -- -- s+le /amp+1 #bh -- mild1 #bc -- pi/ons1 #ai -- -- r+s1 #ai -- tung/51 = valves1 #cj -- ,ubas1 #ij ,/orage ( petrol1 #ajh ,/rap1 ecc5tric1 #cd ,/r5g? & "* ( sp>k1 #eh -- ( mixture1 #a1 #db1 #ajh1 #aji1 #aaj ,/roke1 mean+ (1 #c -- suction1 #f1 #ba1 #ce1 #fj1 #hj ,suction1 mean+ (1 #b ,supplem5t>y coil1 = />t+1 #eh ,surface c>burettor1 #db ,syn*roniz$ ignition1 #ei1 #fa ,t ,tank1 petrol1 #dc ,tap1 compression1 #ac -- petrol1 #dc ,tappet head1 #bi1 #cj -- valve1 #h1 #bi ,tee?1 helical1 #ch -- pit* (1 #ch ,temp]ature ( jacket wat]1 #gd ,t]m9als1 high t5sion1 #ea1 #eg -- l[ t5sion1 #eg1 #eh ,t-head$ cyl9d]1 #ae ,!rmal effici5cy1 #aaj1 #aaa -- unit1 ,briti%1 #aaa ,!rmo-syphon circulation1 #fi1 #hi ,?ree-port two-/roke eng9e1 #ig ,?rottle valve1 #dd1 #dg ,"t lag1 #ef ,tim+ ! ignition1 #fj1 #fb1 #aaf -- ! inlet valve1 #cd1 #cg1 #gh1 #aaf -- ! exhau/ valve1 #ce1 #cg1 #gh1 #aaf -- :eels1 #h1 #cg ,too ri* a mixture1 #df1 #gh ,too weak a mixture1 #df1 #gc1 #gh ,torque1 l[1 #ge ,torsional oscillations ( crank%aft1 #gg ,transf] pipe1 #hf1 #hg ,treasury rat+ = horse-p[]1 #he1 #aja ,trembl] blade1 #eg -- coil1 #eg1 #fa ,tr\ghs1 oil1 #fe ,tube1 am\nt requir$ = radiator1 #gd -- gill$1 #gd -- pla91 #gd ,tung/5-/eel valves1 #cj ,tw9 pi/on two-/roke eng9e1 #if ,two cyl9d] eng9e1 #gf ,two-po9t ignition1 #ei ,two-port two-/roke eng9e1 #ha1 #he1 #ie ,two-/roke cycle1 #hj1 #hc1 #hg -- eng9e1 ,kean1 #he1 #id -- -- simple1 #ha1 #he -- -- tw9 pi/on1 #if -- -- two-port1 #ha1 #he1 #ie -- -- ?ree-port1 #ig -- -- valveless1 #ig ,u ,ubas /eel1 #ij ,unbalanc$ mass1 #be ,und]frame1 #dj ,up-/roke1 #d1 #ha ,v ,vacuum1 p>tial1 #f1 #df1 #di1 #hb1 #ij ,valve1 automatic inlet1 #hb1 #hd1 #hh -- -- extra air1 #dc1 #di1 #hh -- caps1 #ac1 #ca -- defective1 #aac1 #aad1 #aaf -- exhau/1 #e1 #cg1 #ha -- extra air1 #dc1 #di1 #id -- guides1 #h -- head1 #bi -- inlet1 #c1 #e -- me*anically op]at$1 #e1 #cj1 #hd -- mu%room type1 #e1 #h1 #cj -- ne$le1 #dd -- passages1 #aj -- relief1 #fg -- seat1 #ac1 #bi -- spr+s1 #h1 #bi1 #ij -- /em guides1 #h1 #ab1 #ac1 #bi -- tappet1 #h1 #bi -- ?rottle1 #dd1 #dg -- tim+ ! exhau/1 #ce1 #cg1 #gh1 #aaf -- -- ! inlet1 #cd1 #cg1 #gh1 #aaf -- to gr9d 91 #ca -- tung/5 /eel1 #cj ,valves1 noise f1 #cj1 #ci -- poppet1 #bi1 #gg1 #gi -- rot>y1 #gi -- sleeve1 #cb1 #gg1 #gi ,valveless two-/roke eng9e1 #ig ,valve-sett+ diagram1 #aaf ,vanadium /eel1 #bj1 #cf ,vaporization1 #a1 #df1 #dh1 #di1 #id ,vap\r1 inflammable1 #fc -- petrol1 #a1 #cc1 #db1 #hj ,velocity ( air1 #df1 #gj ,v5t pipes1 #ci ,vibration ( crank%aft1 #gf ,viscosity1 #fc ,volatility1 #ajh ,volume displac$ by pi/on1 #aje1 #ajf1 #ajg -- ( cle>ance space1 #d1 #aje1 #ajg ,volumetric effici5cy1 #hc1 #hf1 #hh ,vulcanite fibre tappet head1 #cj ,w ,wa%]1 #bi ,wa/e heat1 #i1 #ag ,wat] boil+ 9 jackets1 #gb -- circulat+ pump1 #h1 #fg1 #ga -- cool$ cyl9d]1 #h1 #cb1 #hb1 #if -- cool+1 int]nal1 #ib -- head (1 #fi1 #ga -- hot1 = jacket1 #dc1 #dg1 #id -- injection1 #ib -- jacket1 #aj1 #ab1 #gj1 #gb1 #gc1 #if -- pipe1 inlet1 #h1 #fi1 #gj1 #ga1 #gc -- -- outlet1 #h1 #fi1 #gj1 #ga1 #gc -- pump1 #h1 #ci1 #dj1 #gb ,wat]-tight jo9t1 #aa1 #ae ,weak5+ ! mixture1 #di1 #gc ,we> on gudgeon p9s1 #ai1 #ij ,webs1 crank1 #bd ,weight ( pi/on1 #ai -- ( wat] 9 radiator1 #gd1 #hi ,weights1 balance1 #be ,:eels1 fibre1 = tim+ ge>1 #ch -- sprocket1 = *a91 #ch -- tim+1 #h1 #cd ,:ipp+ ( crank%aft1 #gf ,wick type ( c>burettor1 #db ,w9d+1 prim>y or l[ t5sion1 #ec1 #eh1 #fa -- second>y or high t5sion1 #ec1 #eh ,wipe =m ( contact break]1 #eh ,wire1 e>?+1 #fj ,wir+ diagram = coil ignition sy/em1 #fa -- -- = magneto ignition sy/em1 #fj ,"w1 #ih -- diagram1 #ajc ,work+ cyl9d]1 #ha1 #hg1 #ajg -- draw+s1 #aa1 #ic ,wri/ p91 #ah 7,,pr4 #acae47 ,butl] ,tann] ,frome & ,london 99 99 99 99 99 ,transcrib]'s ,notes ,obvi\s typographical errors h be5 sil5tly correct$4 ,v>iations 9 hyph5ation h be5 /&>dis$ b all o!r spell+ & punctuation rema9s un*ang$4 ,italics are repres5t$ ?us italic1 bold ?us bold & und]l9+ ?us und]l9e4 ,9 sev]al ( ! equations ! f9al answ] 0 pres5t$ 9 bold text4 ,to avoid confusion ) ! ma!matics ?is has n be5 indicat$4