23 - 1
Loader Valve - Pressure Testing
Main Relief Valve (M.R.V.)
Make sure that the hydraulic oil is at working temperature,
i.e. 50°C (122°F).
Lower the backhoe bucket and loader shovel to rest on the
ground; stop the engine; operate the control levers to vent
residual hydraulic pressure.
1 Connect a 0 - 400 bar (0 - 6000 lbf/in
2
) pressure gauge
to pressure test connector A on the loader valve, (refer
to Service Tools).
2 With the engine running at 1500 revs/min, check M.R.V.
pressure by raising or lowering the loader arms until the
rams are fully open or closed and noting the maximum
gauge reading. CAUTION: Do not select 'float'. The
maximum pressure should be as stated in Technical
Data.
Note: The rams must be 'held' open or closed when reading
gauge.
3 If the pressure is incorrect, loosen locknut D and adjust
screw C. Turn it clockwise to increase pressure and
anti-clockwise to decrease the pressure. When the
pressure is correct, tighten the locknut and check the
pressure again. Adjust as required.
Section E
Hydraulics
9803/3280
Section E
23 - 1
Issue 1
Service Procedures
D
C
A
S266281