Hydraulic Pumps; Lift/Steer Pump - Genie GS-3390 Service Manual

Section 4 • Repair Procedures

Hydraulic Pumps

6-1

Lift/Steer Pump

Note: When removing a hose assembly or fitting,
the O-ring on the fitting and/or hose end must be
replaced and then torqued to specification during
installation. Refer to Section 2, Hydraulic Hose and
Fitting Torque Specifications.
How to Test the Lift/Steer Pump
1 Tag, disconnect and plug the high pressure
hydraulic hose from the lift/steer pump.
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.
2 Connect a 0 to 5000 psi / 0 to 350 bar pressure
gauge to the high pressure port on the lift/steer
pump.
4 - 86
3 Ford models: Close the valve on the LPG tank,
then disconnect the hose from the tank (if
equipped). Move the fuel select toggle switch at
the ground controls to the LPG position.
Deutz models: Hold the manual fuel shut-off
lever clockwise in the closed position.
4 Turn the key switch to ground controls and pull
out the red Emergency Stop buttons to the on
position at both the ground and platform
controls.
5 Observe the pressure gauge while cranking the
engine. Immediately stop if the pressure
reaches or exceeds 3500 psi / 241 bar.
Result: If the pressure gauge reads
3500 psi /241 bar, immediately stop. The pump
is good.
Result: 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.
6 Remove the pressure gauge and connect the
hydraulic hose.
GS-3390 • GS-4390 • GS-5390
a
Deutz models
a manual fuel shut-off lever
Part No. 72863
July 2007
REV D