JLG G6-23A Service Manual - Manual (Page 75)

8.5 G5-19A, G6-23A
Hydraulic System
8.5.2 Main Control Valve Pressure Checking
Attach 5000 psi (345 bar) gauge to the test port (1) on the
main control valve port to check the system pressure.
The main control valve pressure should be 3600 psi (250
± 5 bar) at full throttle.
8.5.3 Charge Pressure Checking
Attach a pressure gauge to the test port (2) on the
hydrostatic transmission to check the system pressure.
The pressure should be 362 to 406 psi (25 to 28 bar) with
the engine at idle.
Do NOT adjust any relief settings. The unit is preset at the
factory and should not be tampered with. If the proper
pressure is not read, the unit may be defective.
8.5.4 Drive Pressure Checking
Attach a pressure gauge to the test fitting (3) on the
hydrostatic transmission to check the system pressure.
Check the drive pressure with the park brake on and the
service brake off at full throttle. The pressure reading
should be 6381 to 6671 psi (440 to 460 bar).
Do NOT adjust any relief settings. The unit is preset at the
factory and should not be tampered with. If the proper
pressure is not read, the unit may be defective.
8.5.5 Steering Pressure Checking
Attach a pressure gauge to the test fitting (4) on the
appropriate hose of the implement pump. The pressure
reading should be 2610 psi (180 bar) with the steering
wheel fully turned to one direction.
Do NOT adjust any relief settings. The unit is preset at the
factory and should not be tampered with. If the proper
pressure is not read, the unit may be defective.
8.5.6 Brake Pressure Checking
Attach a pressure gauge to the test fitting (5) on the brake
valve in the cab to check system pressure. The pressure
reading should be 435 psi (30 bar) with the brake pedal
fully depressed.
Do NOT adjust any relief settings. The unit is preset at the
factory and should not be tampered with. If the proper
pressure is not read, the unit may be defective.
MAH0120
1
MAH0780
2
3
MAH0850
4
MAH0030
5