HYDRAULIC SYSTEM 14000 SERVICE MANUAL
2-28
Published 09-10-14, Control # 065-24
8. Monitor flow meter. Under all operating conditions,
leakage should not be more than 5-1/2 to 6-1/2 gpm
(20,8 to 24,6 L/m).
9. If motor leakage without loop flushing is not within
specified range, replace motor and pump.
10. If motor leakage with loop flushing is not within specified
range, replace loop flushing valve and/or motor and
pump depending on which is the cause for high leakage.
Low Pressure Accessory Adjustment
See Figure 2-29 for the following procedure.
Left travel/drum 3 charge pump #3 is the pressure source for
low pressure accessory systems — swing brake, travel
brake, travel 2-speed, back hitch pins, boom hoist pawl, and
left travel/drum 3 diverter.
If you think that a low pressure accessory system is not
operating properly, proceed as follows:
1. Install an accurate 0 to 1,000 psi (0 to 69 bar) hydraulic
pressure gauge between end of supply line and
corresponding port of actuator (brake port, for example).
Fittings are 06 ORS.
2. Release brake by slowly moving control handle in either
direction to operate corresponding function — pressure
should be approximately 350 psi (24 bar).
3. Apply brake by moving control handle to off — pressure
should be zero.
4. If pressure in step 2 is not between 320 to 370 psi (22 to
25,5 bar), proceed as follows:
a. Loosen lock nut (2).
b. Adjust adjusting screw (3).
- Turn in to increase pressure.
- Turn out to decrease pressure.
c. Start and run the engine at high idle.
d. Repeat above steps until gauge reads no higher
than 375 psi (26 bar).
e. Hold adjusting screw in position and securely
tighten locknut.
5. Stop the engine, remove gauge, and reconnect
hydraulic lines.
Loop Flushing Valve Adjustment
The loop flushing valves for the hoists – load and boom – are
not adjustable. Do not tamper with settings of valve
cartridges in loop flushing valve manifold.
If you are experiencing excessive leakage do to a faulty loop
flushing valve, replace valve.
Manual Override Tests
The pumps, motors, and solenoid valves have manual
overrides that allow electrical problems to be isolated from
mechanical problems when troubleshooting hydraulic
system problems.
Pump or Motor Override
See Figure 2-29 for the following procedure.
1. Start and run the engine at low idle.
2. Rotate manual override (2) in either direction to stroke
pump or motor in corresponding direction.
3. If pump or motor is operating properly, corresponding
side of circuit will stall.
Solenoid Valve Override
See Figure 2-29 for the following procedure.
1. Start and run the engine at low idle.
2. Insert a rigid steel rod through hole in end of valve cap.
3. Depress valve spool with rod.
4. If valve is operating properly, corresponding side of
circuit should operate.
DANGER
Falling or Moving Load Hazard!
To prevent unexpected movement of loads or crane when
operating any manual override:
• Park the crane in an area where it will not interfere
with other job site equipment or structures.
• Land all loads and lower the boom onto blocking at
ground level.
• Park all crane functions.
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