Toro Groundsmaster 3280-D - Page 142

ChargePumpFlowTest(UsingTesterWithPressureGauges
andFlowMeter)(MachineSerialNumbersbelow316000000)
(continued)
6.Ensurethattheowcontrolvalveonthetesterisfullyopen.Also,ensure
thatthetractionpedalandliftvalveareinneutralandthattheparkingbrake
isengaged.
7.Startengineandrunatidlespeed.Checkforanyhydraulicleakagefromtest
connectionsandcorrectbeforeproceedingwithtest.
8.Runengineatfullspeed(3,150to3,250rpm).Useatachometertoverify
thattheenginespeediscorrect.
IMPORTANT
Thechargepumpisapositivedisplacementpump.Iftheowcontrol
valveonthetesterisfullyclosed,transmissiondamagecanoccur.
9.Watchtesterpressuregaugescarefullywhileslowlyclosingtheowcontrol
valveuntilpressuregaugereads3,450kPa(500psi).
10.Flowgaugereadingshouldbeatleast3.8L/minute(1gallon/minute).
11.Openowcontrolvalveontesterandshutoffengine.Recordresultsof
hydraulicowtest.
12.Ifpressureof3,450kPa(500psi)orowof3.8L/minute(1gallon/minute)
couldnotbeachieved,checkthefollowing:
A.Performthechargepressuretest;refertoChargePressureT est(Using
PressureGauge)(MachineSerialNumbersbelow316000000)(page
5–49).Also,adynamicchargepressuretestcanbeperformedtoidentify
ifawornordamagedhydrostatictransmissionexists.
B.Performtheimplementreliefpressuretest;refertoImplementRelief
PressureT est(UsingPressureGauge)(MachineSerialNumbersbelow
316000000)(page5–51).
C.Inspecttheconditionofthechargepumpgerotorandinternalhousing;
refertoChargePumpServiceintheSauer-Danfoss(Sundstrand)15
SeriesServiceManualattheendofthischapter.
D.Thegeneralconditionofthetransmission’spistonpumpandpistonmotor
mightbesuspectedofwearandinefciency.
13.Disconnecttesterfromthetransmissionandhydraulichose.Connect
hydraulichosetothetransmissiontting.Checkhydraulic-uidlevelin
reservoir(frontaxle).
HydraulicSystem:TestingtheHydraulicSystem
Page5–58
Groundsmaster
®
3280-D/3320
05138SLRevB