Toro Groundsmaster 4300-D - Mow Circuit Problems

TractionCircuitProblems(continued)
Problem
PossibleCauses
ThewheelmotordoesnotholdloadintheNEUTRALposition.
Note:Themachinemaynotbecompletelystationaryif
parkedonaninclinewithouttheparkingbrakeengaged.
•Thechargepressureislow.
•Thecheckvalvesinthepiston(traction)pumparedamaged.
•Thevalveplate(s)inthepiston(traction)pumpiswornor
damaged.
•Thewheelmotoriswornordamaged.
Note:If1tractioncircuitcomponenthasinternalwearor
damage,itispossiblethattheothertractioncomponents
arealsodamaged.
Asingle-wheelmotorturnswhileunloaded,butslowsdown
orstopswhentheloadisapplied.
•Thepiston(traction)pumpbypassvalveisopenorleaking.
•Thewheelmotoriswornordamaged.
Note:If1tractioncircuitcomponenthasinternalwearor
damage,itispossiblethattheothertractioncomponents
arealsodamaged.
MowCircuitProblems
Problem
PossibleCauses
Allthe3frontcuttingdeckmotorsdonotoperatebutrear
cuttingdeckmotorsoperate.
•ThesolenoidvalvePRV2ondeckcontrolmanifoldis
damaged.
Note:ThesolenoidvalvesPRV1andPRV2areidenticaland
canbereversedfortestingpurposes.
•AnelectricalproblemexiststhatpreventsPRV2solenoid
coilondeckcontrolmanifoldfrombeingenergized(referto
Troubleshooting(page5–24)ortheElectricalSchematic
andWireHarnessDrawings/DiagramsinAppendixA(page
A–1)).
•Oneormorefrontdeckspindleisbinding.
•Thegearpumpsection(P2)iswornordamaged.
Bothrearcuttingdeckmotorsdonotoperatebutfrontcutting
deckmotorsoperate.
•ThesolenoidvalvePRV1ondeckcontrolmanifoldis
damaged.
Note:ThesolenoidvalvesPRV1andPRV2areidenticaland
canbereversedfortestingpurposes.
•AnelectricalproblemexiststhatpreventsPRV1solenoid
coilondeckcontrolmanifoldfrombeingenergized(referto
Troubleshooting(page5–24)ortheElectricalSchematic
andWireHarnessDrawings/DiagramsinAppendixA(page
A–1)).
•Oneormorereardeckspindleisbinding.
•Thegearpumpsection(P1)iswornordamaged.
Asinglecuttingdeckmotordoesnotoperateorrotates
slowly.
•Thecuttingdeckmotoriswornordamaged.
•Thecross-overreliefvalveinthecuttingdeckmotorisstuck
ordamaged.
Note:Ifappropriate,transferasuspecteddamagedmotor
toanothercuttingdeck.Ifproblemfollowsthemotor,motor
needstoberepairorreplacement.
Groundsmaster
®
4300-D
Page4–41
HydraulicSystem:Troubleshooting
16226SLRevC