Hydraulic Pumps; Hydraulic Pump - Genie GTH-636 Service Manual

Section 4 • Repair Procedures

Hydraulic Pump

6-1
Hydraulic Pump
How to Test the Function Pump
Note: When removing a hose assembly or fitting,
the fitting and/or hose end must be torqued to
specification during installation. Refer to Section 2,
Hydraulic Hose and Fitting Torque Specifications.
1 Tag, disconnect and plug the high pressure
hydraulic hose from the main valve assembly.
Cap the fitting on the main valve.
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.
Note: The high pressure hose is the smaller of the
two hoses.
2 Connect a 0 to 5000 psi / 0 to 350 bar pressure
gauge to the high pressure hose disconnected
in step 1.
3 Hold the manual fuel shut-off lever on the
engine in the closed position.
4 - 44 GTH-636 • GTH-644 • GTH-842 • GTH-844 • GTH-1048 • GTH-1056
4 Observe the pressure gauge while cranking the
engine.
Result:
GTH-636: If the pressure gauge reads
2800 psi / 193 bar, immediately stop. The pump
is good.
GTH-644, GTH-842, GTH-844 and GTH-1056:
If the pressure gauge reads 3000 psi / 207 bar,
immediately stop. The pump is good.
GTH-1048: If the pressure gauge reads
3500 psi / 241 bar, immediately stop. The pump
is good.
Result:
GTH-636: If the pressure fails to reach
2800 psi / 193 bar, the pump or pump coupling
is bad and will need to be serviced or replaced.
GTH-644, GTH-842, GTH-844 and GTH-1056:
If the pressure fails to reach
3000 psi / 207 bar, the pump or pump coupling
is bad and will need to be serviced or replaced.
GTH-1048: If the pressure fails to reach
3500 psi / 241 bar, the pump or pump coupling
is bad 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.
5 Remove the pressure gauge and install the high
pressure hose onto the pump. Torque to
specification. Refer to Section 2, 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.
June 2007
REV B
Part No. 97487