Toro Groundsmaster 4500-D Series - Relieving Hydraulic System Pressure

TowingTractionUnit(continued)
IMPORTANT
Iftowinglimitsareexceeded,severedamagetothepiston(traction)
pumpmayoccur.
Ifitbecomesnecessarytotow(orpush)themachine,tow(orpush)inaforward
directiononlyandataspeedbelow5kph(3mph)andforadistancelessthan
0.4km(0.25mile).Thepiston(traction)pumpisequippedwithtwo(2)bypass
valvesthatneedtobeturnedthree(3)turnscounterclockwisebeforetowingor
pushingthemachine.Thebypassvalvesareonthetopofthepistonpump
(Figure27).Donotturnbypassvalveswhenengineisrunning.
IMPORTANT
Donotloosenreliefvalveswhenengineisrunning.
Beforereturningmachinetoservice,tightenbothofthereliefvalvesuntilseated.
Then,torquereliefvalvesto70N·m(52ft−lb).
IMPORTANT
Ifthemachinemusttobepushedortowedinreverse,thecheck
valveinthereartractionmanifoldmustalsobebypassed.Tobypass
thischeckvalve,connectahydraulichoseassemblytothereverse
tractionpressuretestport,locatedonthepiston(traction)pump,
andontheportlocatedin−betweenportsM8andP2ontherear
tractionmanifoldwhichislocatedbehindthefronttire.UseToropart
numbers95−8843(hydraulichose),95−0985(quantity2)(coupler
tting)and340−77(quantity2)(hydraulictting).
RelievingHydraulicSystemPressure
Beforedisconnectingorperforminganyworkonthehydraulicsystem,all
pressureinthehydraulicsystemmustberelieved.Parkmachineonalevel
surface,makesurethatPTOswitchisOFF ,lowercuttingdecksfully,stopengine
andengageparkingbrake.Waitforallmovingpartstocometoacompletestop.
Systempressureinliftcircuitisrelievedwhenthecuttingdecksarefullylowered.
SystempressureinmowcircuitisrelievedwhenthePTOswitchisdisengaged.
Torelievehydraulicpressureintractioncircuit,turnignitionswitchtoON(engine
notrunning)andmovetractionpedaltobothforwardandreversedirections.
TurnignitionswitchtoOFFafterrelievingtractioncircuitpressure.
Torelievehydraulicpressureinsteeringcircuit,rotatesteeringwheelinboth
directions.
Afterallhydraulicsystempressureshavebeenrelieved,removekeyfrom
ignitionswitch.
HydraulicSystem:GeneralInformation
Page5–4
Groundsmaster
®
4500-D/4700-D
19245SLRevA