Genie GTH-844, Service And Repair Manual

Page: 55 / 187

April 2017 Service and Repair Manual
Transmission
Part No. 1272854 GTH-844 43
6-1
Hydraulic Pump
How t o T est t he Func tion Pump
How to Test the Function Pump
Note: When removing a hose assembly or fitting,
the O-ring (if equipped) on the fitting and/or hose
end must be replaced. All connections must be
torqued to specification during installation. Refer to
Specifications,
Hydraulic Hose and Fitting Torque
Specifications.
Bodily injury hazard. Spraying
hydraulic oil can penetrate and
burn skin. Loosen hydraulic
connections very slowly to allow
the oil pressure to dissipate
gradually. Do not allow oil to
squirt or spray.
1 Connect a 0 to 5000 psi / 0 to 350 bar
pressure gauge to port TP on the secondary
function manifold.
2 Start the engine and fully retract the boom.
Continue to hold the joystick in the boom
retract position and observe the pressure
gauge.
Result: If the pressure gauge reads 3200 psi /
220 bar, immediately stop. The pump is good.
Result: If the pressure fails to reach 3200 psi /
220 bar, the pump needs to be adjusted OR or
the pump or pump coupling is faulty and will
need to be serviced or replaced.
Component damage hazard.
There is no relief valve in the
hydraulic pump and the pump
can be damaged if the pressure
is allowed to exceed
specification. When testing the
pump, crank the engine in one
second intervals until the
correct pressure is confirmed.
Do not over-pressurize the
pump.
3 Remove the pressure gauge and install plug
onto port TP. Torque to specification. Refer to
Section Specifications,
Hydraulic
Specifications .
Bodily injury hazard. Spraying
hydraulic oil can penetrate and
burn skin. Loosen hydraulic
connections very slowly to allow
the oil pressure to dissipate
gradually. Do not allow oil to
squirt or spray.