Hydraulic Oil Can Penetrate And Burn Skin. Loosen Hydraulic; Connections Very Slowly To Allow; The Oil Pressure To Dissipate - Genie GTH-636 Service Manual

June 2007
REV A
16 Start the engine and allow the engine to idle.
Result: The pressure gauge is reads
500 psi / 34.5 bar. The pressure setting is
correct. Proceed to step 17.
Result: The pressure is less than
500 psi / 34.5 bar. The rear lock-up relief valve
(schematic item HH) is failing. Adjust the valve
OR replace the valve.
Result: The pressure is greater than
500 psi / 34.5 bar. Replace the rear lock-up
relief valve (schematic item HH).
17 Stop the engine.
18 Remove both pilot operated directional valves
(schematic items HF and HG) from the rear
lock-up manifold. Inspect the valves.
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.
Result: Both valves do not have broken springs,
or damaged seals. Install the valves. Proceed
to step 19.
Result: The valve has a broken spring or a
damaged seal. The valve is faulty. Replace the
valve.
19 Remove all four check valves (schematic items
HA, HB, HC and HD) from the rear lock-up
manifold. Repair or replace the faulty valve(s).
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.
Part No. 97487 GTH-636 • GTH-644 • GTH-842 • GTH-844 • GTH-1048 • GTH-1056
Section 5 • Troubleshooting
TROUBLESHOOTING
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