Service Manual

TorqueSpecications
Therecommendedfastenertorquevaluesarelistedinthefollowingtables.For
criticalapplications,asdeterminedbyT oro,eithertherecommendedtorqueora
torquethatisuniquetotheapplicationisclearlyidentiedandspeciedinthe
servicemanual.
Thesetorquespecicationsfortheinstallationandtighteningoffastenersshall
applyforallfastenerswhichdonothaveaspecicrequirementidentiedin
theservicemanual.Thefollowingfactorsshallbeconsideredwhenapplying
torque:cleanlinessofthefastener,useofathreadsealant(Loctite),degreeof
lubricationonthefastener,presenceofaprevailingtorquefeature,hardness
ofthesurfaceunderneathofthefastener’shead,orsimilarconditionwhich
affectstheinstallation.
Asnotedinthefollowingtables,torquevaluesshouldbereducedby25%for
lubricatedfastenerstoachievethesimilarstressasadryfastener.T orquevalues
mayalsohavetobereducedwhenthefasteneristhreadedintoaluminumor
brass.Thespecictorquevalueshouldbedeterminedbasedonthealuminum
orbrassmaterialstrength,fastenersize,lengthofthreadengagement,etc.
Thestandardmethodofverifyingtorqueshallbeperformedbymarkingalineon
thefastener(headornut)andmatingpart,thenbackofffastener1/4ofaturn.
Measurethetorquerequiredtotightenthefasteneruntilthelinesmatchup.
FastenerIdentication
InchSeriesBoltsandScrews
Figure1
1.Grade13.Grade8
2.Grade5
POWERMAX®HDServiceManual
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SpecicationsandMaintenance:TorqueSpecications
3424-820RevA