60 GTH-4016SR • GTH-4018SR Part No. 57.4400.9203
March 2010
Section 4 • Repair Procedures
REV A
Main Valve
6-1 How to Remove the Main
Valve
1. Closed the valve of the main hydraulic line. It
is behind the stair for the cabin.
2. Tag the hoses.
3. Remove the connectors.
4. Remove the hoses
WARNING
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. Cap the main valve holes and the hoses holes
6. Remove the main valve screws
7. Support and secure the main valve to a lifting
device of suitable capacity. Do not apply any
lifting pressure.
8. Raise the main valve and laying it on the floor.
6-2 How to Test the Main Valve
1. Insert the 600 bar manometer in the TP1 port,
above the main valve
2. Start the engine.
3. Press the throttle pedal and let the engine
increases up to 2000 rpm.
4. Moving the joystick, retract the boom and
check that the manometer reads 280 bar
5. If not, set the valve placed above the main
valve.