Toro 39678 - Servicing the Spark Plugs

ServicingtheSparkPlugs
ServiceInterval:Every100hours/Yearly(whichever
comesrst)Replacethesparkplugs
ifnecessary.
Type:ChampionRCJ8Y(orequivalent)
AirGap:0.762mm(0.03inch)
Important:Acracked,fouled,dirty,or
malfunctioningsparkplugmustbereplaced.Do
notsand-blast,scrape,orcleanelectrodesby
usingawirebrushbecausegritmayeventually
releasefromtheplugandfallintothecylinder.
Theresultisusuallyadamagedengine.
Note:Removeandinspectthesparkplugsifthe
enginemalfunctions.
RemovingtheSparkPlugs
1.Parkthemachineonalevelsurface,disengage
thePTO,andengagetheparkingbrake.
2.Shutofftheengine,removethekey,andwait
forallmovingpartstostopbeforeleavingthe
operatingposition.
3.Disconnectthespark-plugwires(Figure28).
g001469
Figure28
1.Sparkplug
4.Cleanaroundthesparkplugstopreventdirt
fromenteringtheengineandpotentiallycausing
damage.
5.Removethesparkplugsandthewashers.
CheckingtheSparkPlugs
1.Lookatthecenterofthesparkplugs(Figure29).
Note:Ifyouseelightbrownorgrayonthe
insulator,theengineisoperatingproperly.A
blackcoatingontheinsulatorusuallymeans
thattheaircleanerisdirty.
2.Ifneeded,cleanthesparkplugwithawirebrush
toremovecarbondeposits.
g238425
Figure29
1.Sideelectrode
3.Airgap(nottoscale)
2.Centerelectrodeinsulator
Important:Alwaysreplacethesparkplugs
whenithaswornelectrodes,anoilylmon
it,orhascracksintheporcelain.
3.Checkthegapbetweenthecenterandside
electrodes(Figure29).
Note:Bendthesideelectrode(Figure29)ifthe
gapisnotcorrect.
InstallingtheSparkPlugs
1.Installthesparkplugsandthemetalwasher.
Ensurethattheairgapissetcorrectly.
2.Tightenthesparkplugsto22N∙m(16ft-lb).
3.Installthespark-plugwire(Figure29).
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