Robin FL-H7500 - Insufficient compression; Plug and Ignition; Oil care

53
IV.MALFUNCTIONANDREPAIR
Actiontobedone
Trouble Workorder

Pointtobechecked
Withoutproblem Withproblem
１−１

DoestheCRANKSHAFTrotatebypulling
theRECOILSTARTER?
Yes
２−１
No
１−２
１−２

AnybreakageintheRECOILSTARTER?

No
１−３
RepairtheRECOILSTARTER.
See Ｐ５０〜５２
１−３

DoestheFLYWHEELtouchsomewhere?

No
１−４
IstheclearancebetweentheFLYWHEELandCOILwithinthecriterion
(tolerance:０.３ ±０.１)?Removeforeignmaterialsuchasgravelifany.
See Ｐ４１
１−４

DoestheCRANKSHAFTrotatebyrotating
theFLYWHEELbyhand?
Yes
１−１
Disassembletheenginetoinvestigate.
１−５
１−５

RemovetherockercoverandCOVER,
CAMGEARtotesttheCAMGEAR,etc.for
defects.
Nodefect
１−６
RepairtheVALVE,ROCK ERARM,PUSHROD,CAMLIFTERandCAMGEARif
anydefectswerefound.
See Ｐ３０〜３２(disassemble)、Ｐ４３〜４５(reassemble)
CRANKSHAFTdoesnot
rotate
１−６

AnydefectintheCRANKSHAFT(bearing)
and/ordoesthePISTONseizeup?
Disassemblethewholeengine.BreakageofthebearingsoftheCRANKSHAFTandROD,CONNECTING, and/or
problemsuchthatthePISTONseizesuparelikely.
２−１

IstheSTOPSWITCHON?
Yes
２−２
SwitchtheSTOPSWITCHtoON. 
２−２

RemovethePLUG,SPARKandgroundit.

Doesitigniteifthe 
RECOILSTARTERispulled?
Yes
３−１
No
２−３
２−３

Isthepluggapwithin0.7〜0.8?
Yes
２−４
Adjustthepluggapwithinthecriterionbymovingtheouterelectrode.
Replaceitwithanewoneifnecessary.
２−４

IsthePLUGdirtywithcarbonand/or
gasoline?
No
２−５
CleanthePLUGwithgasolineanddryit.Removecarbon,etc.byawirebrush.
AfterthiscleanthePLUGwithgasolineagainanddryit.
２−５

IsthegapbetweentheCOILand
FLYWHEELwithin(0.3±0.1)?
Yes
２−６
Adjustthegapwithin0.3±0.1.
See Ｐ４１
２−６

DoesanewgroundedPLUGignite? 
Yes
Starttheengine.
No
２−７
PLUGandCOIL
２−７

ReplacetheIGNITIONCOILwithanew
one.
ReplacetheIGNITIONCOILwithanewone.
３−１

AnygasolineintheTANK,FUEL?
Haveyoupushedtheprimerpumptofeed
thegasolinetotheCARBURETOR? 
Yes
３−２
FilltheTANK,FUELwithgasoline.Pushtheprimerpumptofeedthegasolineto
theCARBURETOR.
３−２

HaveyoupulltheRECOILSTARTERwith
thechokeclosedatlowtemperature?
(Theenginewillnotstartwiththick
air-fuelmixtureatlowtemperature.) 
Theenginehasstarted. 
Theenginedoesnotstart.
３−３
３−３

Doestheenginestartbypullingthe
RECOILSTARTERwiththethrottlelever
half-open?
Theenginehasstarted. 
Theenginedoesnotstartyet.
３−４
３−４

Arethefuelfilterand/ortubeclogged?Is
thetubebent?
Notroubleinthefuelpassage.

３−５
Correctthecausesofbadfuelflow.Replacefaultypartswithnewonesif
necessary.
３−５

Isthegasolinefresh?
Yes
３−６
Gasolinestoredinabadwaygoesbadquickly.Oldgasolineshouldbereplaced
withnewone.
Fuel
３−６

DisassembletheCARBURETORtotestit
forthecomponentpartsbeingcloggedup
and/ordeteriorated.
CleantheinsideoftheCARBURETOR,andreplacewearoutpartswithnewonesifnecessary.
See Ｐ４８〜４９
４− １

PulltheRECOILSTARTERtocheckfor
propercompressioninthecombustion
chamber.
Properlycompressed
５−１
Compressedinsufficiently.
４−２
４−２

PulltheRECOILSTARTERswiftly
10-20timeswiththechokeopentostart
theengine.
Theenginehasstarted. 
Stillcompressedinsufficiently.
４−３
４−３

RemovethePLUG.Pullthe
RECOILSTARTERswiftly30-50times.
ScrewthePLUGandstarttheengine.
Theenginehasstarted. 
Stillcompressedinsufficiently.
４−４
４−４

RemovetheROCKERCOVERtocheck
whetherthevalveclearanceiswithin0.08
〜0.40(criterion:0.1−0.15)
Thevalveclearanceis
withinthe
criterion.
４−５
Adjustthevalveclearanceat０.１５.
See Ｐ６１〜６２
４−５

TesttheCAMGEARforanyablationofthe
camtop. 
Noablation
４−６
AnyablationofthecamtopneedsreplacingtheCAMGEARwithanew one.
See Ｐ３０〜３２(disassemble)、Ｐ４３〜４５(reassemble)
４−６

IstheCAMGEARtimingright?(Thetiming
markoftheCAMGEARfacesdown 
verticallywhenthePISTONisatthetop
deadcenter.)
Yes
４−７
CorrectthebadCAMGEARtiming.
See Ｐ４３〜４５
４−７

Disassemblethewholeenginetocheck
whetheranycarbonremainsattachedto
thevalvefaceand/ortheinsideofthe
combustionchamber.
Nocarbonattached
４−８
Removeanyattachedcarbon,ifany.
Insufficientcompression
４−８

TesttheCYLINDERboreandPISTON
RINGformarkedablationand/ordamage.

Noablationordamage
５−１
Markedablationand/ordamageneedsreplacingtheCYLINDER
and/orPISTONRINGwithanewone.
Enginedoesnotstart. 
Unknowncauses ５−１

Askaservicemanwithoutknowncauseoftheenginetrouble.
Workload ６−１

Istheengineoverloaded?
Correctworkload
６−２
Askaservicemanforthecorrectworkload.
６−２

NogasolineintheTANK,FUEL?Haveyou

pushedtheprimerpumptofeedthe
gasolinetotheCARBURETOR?
Yes
６−３
FilltheTANK,FUELwithgasoline.Pushtheprimerpumptofeedthegasolineto
theCARBURETOR.
６−３

Arethefuelfilterand/ortubecloggedup?
Isthetubebent?
Notroubleinthefuelpassage.

６−４
Correctthecausesofbadfuelflow.Replacefaultypartswithnewonesif
necessary.
Pooraccelerationandoutput shortageofengine
Fuel
６−４

IstheinsideoftheAIRCLEANERdirty
withdustand/oroil?
No
６−５
DirtyAIRCLEANERinsidecausesbadengineshaftrevolutionbecauseair
cannotbebreathedwell.See Ｐ ．３６ 〜３７ ．

