Service Manual

TestProcedure
1.Ensurethatthehydraulicuidisatnormaloperatingtemperatureby
operatingthemachineforatleast10minutes.
2.Drivethemachineslowlyinagureeightonaatlevelsurface.
A.Thereshouldbenoshakingorvibrationinthesteeringwheelorrear
wheels.
B.Thesteeringwheelmovementsshouldbefollowedimmediatelyby
acorrespondingrearwheelmovementwithoutthesteeringwheel
continuingtoturn.
3.Stopunitwiththeenginerunning.Turnthesteeringwheelwithsmallquick
movementsinbothdirections.Letgoofthesteeringwheelaftereach
movement.
A.Thesteeringcontrolvalveshouldrespondtoeachsteeringwheel
movement.
B.Whensteeringwheelisreleased,steeringcontrolshouldreturntothe
neutralpositionwithnoadditionalturning.
4.Ifeitheroftheseperformancetestsindicateasteeringproblem,determineif
thesteeringcylinderisdamagedusingthefollowingprocedure:
A.ParkthemachineonalevelsurfacewiththePTOswitchoff,lowerthe
cuttingunits,andsettheparkingbrake.
B.Withtheenginerunning,turnthesteeringwheeltotheright(clockwise)
untilthesteeringcylinderrodisfullyextendedandshutofftheengine.
C.ReadallWarning,Cautions,andprecautionslistedatthebeginningof
thissection.
D.Cleanthettingandhoseend,disconnectthehydraulichosefromthe
ttingontherodendofthesteeringcylinder.
E.Useanelboworateettingwithaholepluggedandinstallapressure
gaugeattheendofthedisconnectedhose.
F.Withtheengineoff,continueturningthesteeringwheeltotheright
(clockwise)withthesteeringcylinderfullyextended.Monitortheopen
ttingonthesteeringcylinderasthewheelisturned.Ifthehydraulicuid
comesoutofthettingwhileturningthesteeringwheeltotheleft,the
steeringcylinderhasinternalleakageandshouldberepairedorreplaced.
5.Thesteeringcircuitreliefvalvelocatedinthesteeringcontrolvalvecanbe
testedwiththepressuregaugeinstalledinthesamelocationasthesteering
cylindertest(step4)asfollows:
A.Starttheengineandrunitatlow-idlespeed.Checkforhydraulic-uid
leaksfromthetestconnectionsandcorrectbeforecontinuingthetest.
B.Settheenginespeedtoapproximately2,000rpm.UsetheInfoCenterto
checkthattheenginespeediscorrect.
IMPORTANT
Holdthesteeringwheelatfulllockonlylongenoughtogeta
systempressurereading.Holdingthesteeringwheelagainstthe
stopforanextendedperiodmaydamagethesteeringcontrol
valve.
C.Monitorthepressuregaugecarefullywhenturningthesteeringwheelfor
arighthandturn(clockwise)andholding.
Groundsmaster
®
4300-D
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HydraulicSystem:TestingtheHydraulicSystem
16226SLRevD