Excavator Valve - Precision Control (Servo)
Pressure Compensator Network - Testing
The pressure compensator valve network can be easily
checked as follows:
1
Start the engine and operate the hydraulic system until
the oil is at working temperature.
2
With the engine at 1500 revs/min operate each service
in turn starting with the service furthest from the pump
inlet section.
If one control valve section function either fails to work
or is slow to work in either one or both directions, the
pressure compensator valve in that section may be at
fault.
When a pressure compensator valve is suspected of
malfunctioning, do the following check:
3
Stall any control valve that is nearer the pump inlet
section than the suspected control valve section. This
should stall the entire system. While at stall operate the
malfunctioning valve section, if the section operates
correctly the pressure compensator valve in question is
at fault.
If the section still malfunctions the pressure
compensator valve is NOT at fault.
Note:
The pressure compensator valves may be removed for
inspection, refer to
Excavator Valve - Dismantling and
Assembly
. Clean and refit, or fit a new pressure
compensator valve as required.
23 - 12
Section E
9803/3280
Section E
23 - 12
Issue 1
Service Procedures
