Toro 74492 - Purging Procedure; Tracking Adjustment

AdjustingtheMotionControlLinkage(NeutralSetting)(continued)
14.Raisethemowerdeckandinstalltheheight-of-cutpin.
15.Checkforproperoperationandensurethatthemachinedoesnotcreepin
neutralwiththeparkbrakedisengaged.
TrackingAdjustment
1.DisengagethePTOswitch.
2.Drivetoanopen,atareaandmovethemotioncontrolleverstothe
neutral-lockposition.
3.MovethethrottlemidwaybetweentheFASTandSLOWpositions.
4.Movebothmotioncontrolleversfullyforwarduntiltheybothhitthestops
intheT-slot.
5.Observewhichdirectionthemachinetracks.
6.Ifthemachinetrackstotheright,inserta3/16inchhexwrenchthrough
theaccessholeintherightfrontcoverpanelandrotatethetrackingscrew
clockwiseorcounterclockwisetoadjustthetravelofthelever.
7.Ifthemachinetrackstotheleft,inserta3/16inchhexwrenchthrough
theaccessholeintheleftfrontcoverpanelandrotatethetrackingscrew
clockwiseorcounterclockwisetoadjustthetravelofthelever.
8.Drivethemachine,checkthefullforwardtracking.
9.Repeattheadjustmentuntilthedesiredtrackingisobtained.
PurgingProcedure
Duetotheeffectsairhasonefciencyinhydrostaticdriveapplications,it
iscriticalthatitbepurgedfromthesystem.Thispurgeprocedureshould
beimplementedanytimeahydrostaticsystemhasbeenopenedtofacilitate
maintenance,anyadditionaloilhasbeenaddedtothesystem,orareplacement
transaxlehasbeeninstalled.Aircreatesinefciencybecauseitscompression
andexpansionrateishigherthanthatoftheoilinhydrostaticdrivesystems.
Theresultingsymptomsinthehydrostaticsystemmaybe:
•noisyoperation
•lackofpowerordriveafterashortperiodofoperation
•highoperatingtemperatureandexcessiveexpansionofoil,inthelattercase,
oillevelmaybehighintheexpansiontankoroverow
Thefollowingprocedureshouldbeperformedwiththewheelsoffthegroundand
thenrepeatedunderoperatingconditions.
1.Withthebypassvalveopen(pushposition)andtheenginerunning,slowly
movethedirectionalcontrols(forward/reverselevers)inbothforwardand
reversedirections5-6times,asairispurgedfromthetransaxles,theoil
levelwilldrop.
2.Withthebypassvalvesintheclosedposition(runposition)andtheengine
running,slowlymovethedirectionalcontrolleversinbothforwardand
reversedirections5-6times.
3.Itmaybenecessarytorepeatsteps1and2untilallairiscompletelypurged
fromthetransaxles.Whenthetransaxlesmoveforwardatnormalspeed,
purgingiscomplete.
2000SeriesZMASTER®ServiceManual
Page7–7
DriveSystem:ServiceandRepairs
3438-778RevA