Toro 08743 - Servicing a Hydraulic Cartridge Valve

ServicingaHydraulicCartridgeValve
Removethefollowingmanifoldsfromthemachinebeforeremovingthecartridge
valves;refertoTractionReliefManifold(page5–83),RearLiftReliefManifold
(Model08743)(page5–85),orHydraulicSwitchKitManifold(Optional)(page
5–117).
TheoptionalRearRemoteHydraulicsManifoldisdifculttoremove;referto
RearRemoteHydraulicsManifold(Optional)(page5–115).Carefullyservicethe
rearremotehydraulicssolenoidvalvewiththemanifoldinplace.
Note:Forsolenoidstylecartridgevalvecoiltestinginformation;refertoHydraulic
SolenoidValveCoils(Optional)(page6–23).
1.Ensurethatthemanifoldiscleanbeforeyouremovethecartridgevalve
fromthemanifold.
2.Removethecartridgevalve:
A.Forsolenoidstylevalves,disconnectthewireharnessconnectorand
removethenutthatsecuresthesolenoidcoiltothecartridgevalve.
Carefullyslidethecoiloffthevalve.
IMPORTANT
Handlethecartridgevalvecarefully.Slightbendingordistortion
ofthestemtubecancausebindingandmalfunction.When
removingthecartridgevalvefromthemanifold,ensurethatthe
deepwellsocketfullyengagesthevalvebase.
B.Useadeepsocketwrenchtoremovethecartridgevalvefromthe
manifold.
3.RecordthecorrectlocationoftheO-rings,thesealingrings,andtheback-up
rings.Removeanddiscardthesealkitfromthecartridgevalve.
4.Visuallyinspectthemanifoldportandthecartridgevalve:
A.Checkfordamagedthreadsonthecartridgevalveandinthemanifold
block.
B.Ifvalvesealingsurfacesappearpittedordamaged,thehydraulicsystem
maybeoverheatingortheremaybewaterinthesystem.
C.Contaminationmaycausevalvestostickorhangup.Contamination
canbecomelodgedinsmallvalveoricesorsealareascausingvalve
malfunction.
CAUTION
Useeyeprotectionsuchasgoggleswhenusingcompressedair.
Note:Particlesasneastalcumpowdercanaffecttheoperationofhigh
pressurehydraulicvalves.
5.Cleanthecartridgevalve.
A.Fornon-solenoidoperatedvalves:Submergethevalveincleanmineral
spiritstoushoutcontamination.Ifthevalvedesignallows,usea
non–metallicprobetopushtheinternalspoolinandout20to30times
toushoutcontamination.Cleananddrythecartridgevalvewith
compressedair.
B.Forsolenoidoperatedvalves:Temporarilyinstallthesolenoidonthe
cartridgevalveandconnecta12voltpowersourcetothesolenoid.
SandPro
®
3040and5040
Page5–87
HydraulicSystem:ServiceandRepairs
20251SLRevA