Service Manual

CuttingUnitCircuitTesting–ReliefValveTest(continued)
Cuttingunitcircuitpressureandreliefvalveoperationistherstinaseriesof
testsrecommendedtocheckcuttingdeckcircuitperformance.Theresults
fromthistestwillhelpdeterminewhichcomponent(s)arethecauseofcutting
unitperformanceissues.
Note:Formachineswithbacklap,thereliefvalveispartofthesolenoidvalve
(S1R1).
Testingtheperformanceofthesolenoidvalve(S1R1)relieforreliefvalve(R1)
ensuresthatthemaximumamountofuidisavailabletothecuttingunitmotors
uptothesetreliefpressure.Thistestalsoensuresthatpump(P2)iscapableof
generatingenoughpressuretoopenaproperlyfunctioningreliefvalve.
SpecialEquipmentRequired:
•FlowMeterwithPressureGaugethathasatleasta45LPM(12GPM)
capacity.
•Phototach(non−contacttachometer).
1.Parkthemachineonalevelsurfacewiththecuttingunitslowered.Make
suretheengineisOFFandtheparkingbrakeisengaged.
2.ReadandadheretotheinformationprovidedinT estingtheHydraulicSystem
(page4–35).
g216862
Figure39
1.Hydraulichose2.Bulkhead
3.Disconnectthehydraulichosefromthebulkheadatthefrontofthemachine;
refertoFigure39.
4.Installtesterinserieswiththebulkheadandthedisconnectedhose.Make
surethetesterisinstalledinthecorrectowdirectionandthetesterow
controlvalveisfullyopen.
5.Topreventreeldamage,temporarilyadjustbedknifetoallowclearance
betweenbedknifeandreel(nocontact)onallthreecuttingunits.
6.Formachineswithbacklap,recordthecurrentreelspeedsettingthensetthe
reelspeedtothehighestspeed(fullyopen).Thebacklapknobonthemower
manifoldmustbeintheMOWposition.
HydraulicSystem:TestingtheHydraulicSystem
Page4–54
Greensmaster3120
17230SLRevD