Genie GTH-1048, Service Manual

Page: 127 / 214

Section 4 • Repair Procedures March 2015
4 - 58 GTH-1048 • GTH-1056 Part No. 123701
MANIFOLDS
7-8
Valve Adjustments -
Secondary Function Manifold
How to Set the Steer System
Pressure
Note: Be sure that the hydraulic oil level is visible
in the inspection glass of the hydraulic tank.
1 Install a 0 to 1000 psi / 0 to 100 bar pressure
gauge into test port 'TP' at the top of the
primary function manifold (schematic item AAA
or BZ). See 7-1 or 7-2,
Primary Function
Manifold Components.
2 Start the engine. Allow the engine to idle after
warming the engine to operating temperature.
3 Without operating any machine controls,
observe the reading on the pressure gauge.
Result: The pressure gauge reads
450 ±25 psi / 31 ±1.7 bar. The pump is
functioning correctly.
Result: The pressure gauge fails to read
450 ±25 psi / 31 ±1.7 bar. The pressure setting
needs to be adjusted. See Repair Procedure
6-1,
How to Adjust the Function Pump
Pressure.
4 Turn the machine off. Remove the pressure
gauge from the test port.
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.
5 Install a 0 to 3500 psi / 0 to 250 bar pressure
gauge into test port 'TS' at the top of the
secondary function manifold (schematic item
CR). See 7-3,
Secondary Function Manifold
Components.
6 Start the engine. Allow the engine to idle.
7 Fully turn and hold the steering wheel in the left
direction and allow the wheels to fully turn to
the left. Continue holding the steering while
observing the pressure reading on the pressure
gauge.
Result: The pressure gauge reads
2500 psi / 172 bar. The pressure setting is
correct. Proceed to step 12.
Result: The pressure gauge fails to read
2500 psi / 172 bar. The pressure setting needs
to be adjusted. Proceed to step 8.
8 Turn the machine off. Hold the steer pressure
reducing/relief valve with a wrench and remove
the cap (schematic item CD).
9 Adjust the internal hex socket. Turn it clockwise
to increase the pressure or counterclockwise to
decrease the pressure.
Component damage hazard. Do
not adjust the relief valve
pressures higher than
specifications.
10 Install the relief valve cap.
11 Repeat this procedure beginning with step 6.
12 Turn the machine off. Remove the pressure
gauge from the test port.
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.