Toro Groundsmaster 4500-D Series - Page 156

ProcedureforReverseTractionCircuitReducingValve(PR)PressureTest
Note:Wheninreverse,pressurereducingvalve(PR)limitsthepressuretothe
rearaxlemotorto31bar(450PSI)sotherearwheelswillnotscufftheturf.
CAUTION
Preventpersonalinjuryand/ordamagetoequipment.Readall
WARNINGS,CAUTIONSandPrecautionsforHydraulicTestingatthe
beginningofthissection.
1.Makesurehydraulicoilisatnormaloperatingtemperaturebyoperating
themachineforapproximatelyten(10)minutes.Makesurethehydraulic
reservoirisfull.
2.Parkmachineonalevelsurfacewiththecuttingdecksloweredandoff.Make
sureengineisoffandtheparkingbrakeisengaged.
Note:The#6zeroleakplugontheinsideofreartractionmanifoldisazero
leakplugthathasataperedsealingsurfaceontheplughead.Lightlyrap
theplugheadusingapunchandhammerbeforeusinganallenwrench
toremovetheplug:theimpactwillallowplugremovalwithlesschanceof
damagetothesocketheadoftheplug.
g308369
Figure65
1.Frontframe2.Reartractionmanifold
3.Locatereartractionmanifoldthatisattachedtothefrontframenexttothe
leftsidefrontwheel(Figure65).Remove#6zeroleakplugontheinsideof
reartractionmanifoldandinstalldiagnostictting(T oropartnumber59-7410)
intomanifoldport.
4.Connecta70bar(1000PSI)pressuregaugewithhydraulichoseattached
toinstalleddiagnostictting.
5.Startengineandincreaseenginespeedtohighidlespeed.Makesurethat
Auto/LOWmodeswitchisintheLOWspeed(mow)positionandrelease
parkingbrake.
6.Sitonseat,applybrakesfullyandslowlydepressthetractionpedalinthe
reversedirection.Whilepushingtractionpedal,carefullymonitorthepressure
gaugetoidentifytheopeningpressureofthepressurereducing(PR)valve:
GAUGEREADINGTOBE29to32bar(420to470PSI)whenthepressure
reducing(PR)valveopens.
HydraulicSystem:Testing
Page5–54
Groundsmaster
®
4500-D/4700-D
19245SLRevA