Toro Groundsmaster 4500-D Series - Page 163

ProcedureforPiston(Traction)PumpFlowTest(continued)
3.Thoroughlycleanjunctionofhydraulichoseandrightsidettingonbottom
ofpistonpump(forwardport)(Figure71).Disconnecthosefromrightside
pumptting.
4.Installtesterwithpressuregaugeandowmeterinseriesbetweenpiston
pumpttinganddisconnectedhosetoallowowfromtractionpumptotester.
Usehydraulichosekit(seeSpecialTools(page2–16))toconnecttesterto
machine.Makesurethatttingandhoseconnectionsareproperlytightened.
Also,makesuretheowcontrolvalveontesterisfullyopen.
5.Startengineandincreaseenginespeedtohighidlespeed.
6.Slowlypushtractionpedaltofullyforwardposition.Keeppedalfully
depressedinthefullyforwardposition.
7.Havesecondpersonwatchpressuregaugeontestercarefullywhileslowly
closingtheowcontrolvalveuntil69bar(1000PSI)isobtained.Verifywith
theInfoCenterdisplaythattheenginespeedisstillatthecorrecthighidle
speed.
Note:Ifenginespeeddropsduringtesting,pumpowwilldecreaseand
owtestresultswillbeinaccurate.
8.Observeowgauge.Flowindicationshouldbeapproximately113LPM(30
GPM).
9.Releasetractionpedaltotheneutralposition,openowcontrolvalveon
testerandshutoffengine.Recordtestresults.
10.Ifowislessthan91LPM(24GPM),considerthefollowing:
A.Thetractionpedalisnotcalibratedcorrectly(seeTractionPedalPosition
SensorCalibration(page6–21)).
B.Thepistonpumpswashplateisnotbeingrotatedfully(e.g.traction
speedisnotsetto100%).
C.Theforwardtractionreliefvalveisleakingorfaulty.
D.Thepistonpumpneedstoberepairedorreplacedasnecessary.
11.Makenecessaryrepairsbeforeperforminganyadditionaltractioncircuittests.
12.Whentestingiscomplete,disconnecttesterfrompumpttingandmachine
hydraulichose.Reconnecthosetopumptting.Lowermachinetoground.
Groundsmaster
®
4500-D/4700-D
Page5–61
HydraulicSystem:Testing
19245SLRevA