Toro 74920 - Cleaning the Cooling System

checkandadjusttheairgap.Installanewsparkplug(s)
ifnecessary.
Type:NGKBPR4ES(orequivalent)
AirGap:0.030inch(0.76mm)
RemovingtheSparkPlug
1.DisengagethePTO,movethemotioncontrollevers
totheneutrallockedpositionandsettheparking
brake.
2.Stoptheengine,removethekey,andwaitforall
movingpartstostopbeforeleavingtheoperating
position.
Figure48
Note:Duetothedeeprecessaroundthespark
plug,blowingoutthecavitywithcompressedair
isusuallythemosteffectivemethodforcleaning.
Thesparkplugismostaccessiblewhentheblower
housingisremovedforcleaning.
CheckingtheSparkPlug
Important:Nevercleanthesparkplug(s).Always
replacethesparkplug(s)whenithas:ablack
coating,wornelectrodes,anoilylm,orcracks.
Ifyouseelightbrownorgrayontheinsulator,the
engineisoperatingproperly.Ablackcoatingonthe
insulatorusuallymeanstheaircleanerisdirty.
Setthegapto0.030inches(0.76mm).
G008794
1
2
Figure49
InstallingtheSparkPlug
Tightenthesparkplug(s)to16ft-lb(22N-m).
16ft-lb
22N-m
G010687
Figure50
CleaningtheCoolingSystem
Cleantheairintakescreenfromgrassanddebrisbefore
eachuse.
1.Disengagethebladecontrolswitchandmovethe
controlleverstotheneutrallockedpositionand
applytheparkingbrake.
2.Stoptheengine,removethekey,andwaitforall
movingpartstostopbeforeleavingtheoperating
position.
3.Removetheairintakescreen,aircleanercover,and
fanhousing.
4.Cleandebrisandgrassfromtheparts.
5.Installtheairintakescreen,aircleanercover,and
fanhousing.
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