Toro Greensmaster 3120 - Page 108

Steering/LiftCircuitTesting–GearPump(P3)FlowandCircuit
ReliefValveTest(continued)
C.Recordtesterpressureandowreadingsunderload.
D.Openowcontrolvalvefully.
E.Theunderloadtestowreading(stepB)shouldnotdropmorethan
15%whencomparedtothepumpatnoloadtestowreading(stepA).A
differenceinowofmorethan15%,ortheinabilitytoachievespecied
pressuremayindicatearestrictioninthepumpintakeline,orthatthe
gearpump(P3)iswornandshouldberepairedorreplaced.
10.Testthecircuitreliefvalveasfollows:
CAUTION
Whenperformingthetest,donotallowthesystempressureto
exceed8300kPa(1400PSI).
IMPORTANT
Holdsteeringwheelatfulllockonlylongenoughtoobtaina
systempressurereading.
A.Openthecircuitreliefvalveviathesteeringsystem.Watchthepressure
gaugeonthetesterandturnthesteeringwheelcompletelyinone
direction.Thecircuitreliefvalveshouldopenjustaftertherearwheel
getstothefulllockposition.Recordthepressureatwhichthereliefvalve
opens.
B.Openthecircuitreliefvalveviatheliftsystem.Watchthepressure
gaugeonthetesterandmovethejoystickcontroltotheRAISEposition.
Momentarilyholdthejoystickwiththecuttingunitsfullyraisedcausing
thecircuitreliefvalvetoopen.Recordthepressureatwhichtherelief
valveopens.
C.SetthejoysticktotheNEUTRALpositionandturntheengineOFF.
Note:Thecircuitreliefvalveisinserieswithchargereliefvalve.Charge
reliefpressurewillaffectthecircuitreliefpressure.
D.Thecircuitreliefvalvepressureshouldbe7300to8600kPa(1050to
1250PSI)higherthanthechargereliefvalvepressure(e.g.ifthe
chargereliefvalvepressureis414kPa(60PSI),thecircuitreliefvalve
pressureshouldbefrom7653to9032kPa(1110to1310PSI).
Note:TheLoweringCuttingUnitsReliefValveT estisperformedwiththe
testerinstalledinitscurrentlocation.RefertoSteering/LiftCircuitT esting
–LoweringCuttingUnitsReliefValveTest(page4–63)foradditional
information.
11.Whentestingiscomplete,removetesterandconnecthosetopumptting.
12.Checkuidlevelinhydraulictankandadjustasnecessary;refertotraction
unitOperator’sManual.
HydraulicSystem:TestingtheHydraulicSystem
Page4–62
Greensmaster3120
17230SLRevC