Walbro - Vintage Snow

1 WalbroDIAPHRAGMCARBURETORS w albrnEngineManagementA ftermarke t DivisionINTRODUCTION2 AIR ANDFUEL3 ALTERNATIVEFUELS4 TWO-CYCLEENGINES5,6 THEFUELMETERING SYSTEM6,7 BUTTERFLYVALVECARBURETORS7,8 VENTURIOPERATION8 TROUBLESHOOTING9 12 DeterminingCause9,10 :11 Poor Idle12 PoorAcceleration12 Poor High Speed:12 CarburetorDisassembly12,13 CARBURETORREBUiLD13,14 MixtureScrews13 Fuel Pump14 Welch Plug Removal:14 MAINNOZZLECHECKVALVE15-17 REASSEMBLy18 PRESSURE TESTING19 ADJUSTMENTS20 BARRELVALVECARBURETORS21WY SERIES22WZ SERIES23 BARRELVALVECARBURETORADJUSTMENTS24 AIR PURGESySTEMS25 PRIMERSySTEMS26, 27 ACCELERATORSySTEMS28, 29 GOVERNOR30 TOOLS31_____ _____Walbro corporation 1 Asdi verseasIheW, 'Oducin ,Imanual10detailtherepairoreachspecificW aIbn>carburetorwouldbeImonumentaltask,an dthemanualwoul dbeobsole teas soon1$trwasprimed.

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4 Uw'e~all'< ,10cokletuproducc:l;llllX1:~ FuelsrusnyfueltooomnlOStcfro:icndyil '",,>!beiXlffibinodwithaspcciriu:KnOlln,ofair . This1;{ICCiro:;oir/f" cl mtio"' calledthest<>ic:hionlCltie,(1mprc>.<yoorfrk" d'wi~til.:ll oocl)For ,a.",lillC, f a i'(orwoe"poondof&l'S01iO AIthismo011thea vailtblcai .iscombinedwilhalltileaoaibblcP'O'-meCOcat/ <ls0U1ortheC< "ortuBalclr , :wi!rnswvi"""""'i!l&IIlIbts..6:1f3liD; > >c:10.! ;(llclratioIMt is . bit. icb< " Olt"rIlQr&fueJ1h:lnthoc~ ~.M<>Slc~iJICs< ' :1 1012:1,,,,(Wid -ingthem"' i' ha bitorCX(c:<.))))}

5 'f"" >cc~traf",,1i~uSC(1to~001mecylin dercomponents<I, inceIIOme[" ':1.>100.~.rich,'lCt,ln g,emi$Sioru;archigbct.,1 IlP'J"VI"i$~Iigtli lyIc5s;W(:woOlthe:eog inellI,unjuS!ric"CIIOUgh10t CI" lhcmi"wealwhichthearl>w1:lIlri.~gc".r-a1 lrXl.(')ppositc:aI'.1 """ laO"' <>,na' ' I>c:aotbc"", $Iosc:.tl>eir0fIC".1ti ,,&tOlc"""",,aodoci .Hllfenginesareala> ,ancxplo vcnbamingor lhcruc:l"'ilhintllCc )'Ii,~ <:tOO~tinnI"'t'exu-emeIood~or,engir\e pan. c. u, i'l<:them' 0 r" ,IllI1 ICtimeIued~ IliPpM~~IDPOO )~I:be~ >of~ ~lhInp$<> ( 13ooof6.)]

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7 Thi' d,alc(J/l(llfueledenginesrun cooler~.n 150-liMeng i nes. SUI keepinmindlI1alifa n CnllineisrunOOllk<h> "" ') :encinewillberunning1_andllDuu .WallI<oarbwellllfSandcrlolll!!bekplirniuof_QbDIs~illI<ldaysIIIds:I~cWnol, I"of! '-cuMlllE(Methyl TertiaryIltitylElbc:t).Card=bIi:nd,ngQIIJ(lmCtimesnt:Al~irl~Uceedinllhc:Je1c>dsOdalocalbasi$.Yo , iallllhetipoftheinletn<>e<ile.<isno'"IredcoloredvilOf\,and1I1. 1several fuel pump madefl'lld'labrown eolored"""""nm,.. """=developed10in=aselheakohol=islanoedo wcarboa" ~.))

8 ,..nil~yhoftdleI~ < ~awIica1icft,..~)'OlIl;OJIl~talocal~.<IlIlpforadvia:0I:l~ >1lond iscussiononairandfuellhat (WIlydoesilm"ntaln I""'Stanlproper l ir:f",,1ralia.; ,~ro"lbolnallthevariOllSspeed!, theeIllinef~W > ",.. '''' ,.. ,..pi""'"---~,_ ,.fIIlng"'".,",,~..,,..I\ ""'"""~"'""OM'"_to,_k>ol-_.,-'.. ,.,.I'.. 1 EFli/oIGOIAPHAAGIIREEDVA LVEI~OUCTlOllFUELPUMP~ ,~=INTAKEAlRc::J. 0,~.pi""'"_ _"P,"~0l>o<I<00""'""';~,..-" ,.._,,""-,..~-PISTONPOIlllNOUCJ1 OOIREPl ' 01' , "ar'lL3i<'ofthe2<ydeengino.

9 Sinceildoesn' tR;:ly00 p' \L' ;UUle, :" (lJICl'alCInIllyPQ$iUon_laonIerII>ope:tl Ileinanypo')liIioon,LbeS)'SlOtllSoonn:aI Iydependingan&n'".y( """ '".yRowfuel$)"..)nec:d10beIq:h:ul"'iIhme clIani aIdc>' ~~ "melerilocdi1pho4llla:ldIISCS" fuelpumpilIp1 Inductio n on t heTwo-CycleEngineTheR;:lifelhrocbasicfor msdindoctioo""the2_t)'tleengine:n:Ka/)'" a1ve.'"'""val""andpisIoIlporICd,We' lldil:l:1 ISS'"'""valveandjlisIonponbcresinceIhe$e _!bemost00Ih0II<lIIilltbl:. ""lYeSarer:eneraJlyfwndoaly011 IlIlltOII:yI:IQand_ ~ist~by!

10 >,but".! \ !be" ~asaDa:aleJ'Il'llJIinI.~pumpoi:lgiscnadb yeepU-lI' :bl01pIasIic:malislIKIlI1O~ :IOI,anddoeso',RowbackllW011ee~lUtlkeo/i bepi$lon.~piSlOQportedeagine arlowl! ,."' ~TheFuel PumpSystem'"'"pQ<I'Cf10llJlt>"EIbefuelP< ,vac:uwnpul$l:smaw:! 'elIPofthediafllIrI&mbubbleand"JerieIale lleck valYel-The:ruelpumpptOYldespeasun:lYbicb !beJCSI oflbearbureaordepends( $",ialO!becylinderiltrealCl low~IrQin! , ,.,""'" JthroogI!\!Ieimpulse~anddrawsupanlllepum p d; aphragmcteating ."lIC<, ~JDeri;;airpr=;ser-lowod;nlO!)