Toro 29521 - Servicing the Spark Plug

ServicingtheSparkPlug
ServiceInterval:Every160hours
TypeforallEngines:NGKBPR4ESorequivalent
AirGap:0.75mm(0.03inch)
Makesurethattheairgapbetweenthecenterand
sideelectrodesiscorrectbeforeinstallingthespark
plug.
Useasparkplugwrenchforremovingandinstalling
thesparkplug(s)andagappingtool/feelergaugeto
checkandadjusttheairgap.Installanewspark
plug(s)ifnecessary.
RemovingtheSparkPlug
1.Shutofftheengine,engagetheparkingbrake,
removethekey,andwaitforallmovingpartsto
stopbeforeleavingtheoperatingposition.
2.RemovethesparkplugasshowninFigure43.
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Figure43
CheckingtheSparkPlug
Important:Donotcleanthesparkplug(s).
Alwaysreplacethesparkplug(s)whenithasa
blackcoating,wornelectrodes,anoilylm,or
cracks.
Ifyouseelightbrownorgrayontheinsulator,the
engineisoperatingproperly.Ablackcoatingonthe
insulatorusuallymeansthesparkplugisdirty.
Setthegapto0.75mm(0.03inch).
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Figure44
InstallingtheSparkPlug
Tightenthesparkplug(s)to22N∙m(16ft-lb).
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Figure45
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