Service Manual
Whentheengineisshutoff,theover−runninginertialoadoftheenginecooling
fanbladeskeepsdrivingthefanmotorandturnsitintoapump.Thecheck
valve(CV1)inthecombinationmanifoldwillopentokeepthemotorcircuitfullof
oilsothefanmotorwillnotcavitate.
ForwardDirectionFanOperation
Duringnormal,forwarddirectionfanoperation,circuitoilowissentthroughthe
de−energizedsolenoidvalve(S10)inthecombinationmanifoldtorotatethe
coolingfanmotor.Returnowfromthemotorre−entersthemanifold(portM2),
throughthede−energizedsolenoidvalve(S10),totheoillterandthenoutof
themanifold(portCH2).Afterexitingthemanifold,circuitoilisroutedtothe
tractionchargecircuit.
ReverseDirectionFanOperation
TheTECcontrollercanreversethecoolingfantocleandebrisfromtherear
intakescreen.Ifhydraulicoiland/orenginecoolanttemperaturesincreasetoan
unsuitablelevel,ahighPWMsignalissenttothe(PRV)valvetoslowthecooling
fananddirectallpumpoilowtothetractionchargecircuit.Thecontrollerthen
energizessolenoidvalve(S10)inthecombinationmanifoldtoreversecooling
fanmotoroilowsothatthemotorrunsinthereversedirection.AlowerPWM
signalissenttothe(PRV)valveallowingoilowtoreturntothefanmotorbutin
thereversedirectioncausingthemotorandcoolingfantoruninreverse.The
controllerdeterminesthelengthoftimethatthefanshouldberuninreverse
beforefanrotationisreturnedtotheforwarddirection.
Note:Theoperatorcanmanuallycausethecoolingfantoreverseby
simultaneouslypressingtherightandleftbuttonsontheInfoCenterdisplay.
Groundsmaster
®
4100-D&4110-D
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HydraulicSystem:HydraulicFlowDiagrams
13203SLRevF