Lull 944E-42 Service Manual - Manual (Page 149)

8-33 944E-42
Hydraulic System
6. Install the load shuttle cartridge (2), with new seals
and torque to 20 lb-ft (27 Nm).
7. Install the accumulator charge logic cartridge (3),
with new seals and torque to 28 lb-ft (38 Nm).
8. Install the direct acting relief valve (4), with new
seals and torque to 20 lb-ft (27 Nm).
9. Install the inverted shuttle cartridge (5), with new
seals and torque to 28 lb-ft (38 Nm).
10. Place the orifice disc (6) in the port and install the
pilot directional cartridge (7) with new seals and
torque to 20 lb-ft (27 Nm).
11. Install the new sintered filter (8) followed by the
washer (9) into the port. Secure in place with the
filter retainer (10) and o-ring (11). Torque the retainer
to 18-22 lb-ft (24-30 Nm). Tighten the filter nut (12)
and torque to 27-29 lb-ft (37-39 Nm).
12. Install the load sense compensator (13), with new
seals and torque to 50 lb-ft (68 Nm).
13. Install the two check valves (14), with new seals and
torque to 20 lb-ft (27 Nm).
14. Install the pressure reducing cartridge (15), with new
seals and torque to 20 lb-ft (27 Nm).
15. Install the coil assembly (16), with new seals and
torque to 20 lb-ft (27 Nm).
16. Install the accumulator brake pressure switch (17),
with new seals and torque to 15 lb-ft (20 Nm).
c. Accumulator Charge/Secondary Function Valve
Installation
1. Reassemble all remaining fittings and test ports to
the accumulator charge/secondary function valve.
2. Align the accumulator charge/secondary function
valve with the carriage bolts in the mount holes on
the valve plate assembly. Tighten both carriage
bolts.
3. Connect all the previously labeled hydraulic hoses,
fittings, wire terminal leads, etc., to the accumulator
charge/secondary function valve.
4. Check the routing of all hoses and wiring for sharp
bends or interference with any rotating members,
and install tie wraps and/or protective conduit as
required. Tighten all hose clamps.
5. Lift valve plate up and secure in position under cab.
Refer to Section 4.7.2, “Valve Plate Installation,” for
installation procedure.
6. Properly connect the batteries
7. Start the engine and run at approximately 1/3-1/2
throttle for about one minute without moving the
machine or operating any hydraulic functions.
8. Inspect for leaks and check the level of the hydraulic
fluid in the reservoir. Shut the engine OFF.
9. Wipe up any hydraulic fluid spillage in, on, near and
around the machine, work area and tools.
10. Close and secure the engine cover.
d. Accumulator Charge Test
Conduct a pressure check of the accumulator circuit.
Refer to Section 8.3, “Hydraulic Pressure Diagnosis.”
8.7.14 Accumulators
This section covers the testing and charging of the
accumulator system.
The accumulators are located under the floor of the cab
and are mounted to the valve plate. The internal parts of
these accumulators are not serviceable. If the internal
diaphragm is leaking, or the seals on the top or bottom
cap are leaking, the accumulator requires replacement.
The accumulator pre charge pressure will vary depending
on the ambient temperature that the accumulators were
pre-charged at and the actual operating temperature of
the accumulators. The following table shows how the pre-
charged pressure can be affected by temperature range.
The following table depicts the accumulators pre-charged
to 450 psi (3103 kPa), at a baseline temperature of 70° F
(21° C).
MU2001
4
7
2
3
6
5
15
16
14
8
11
12
10
9
13
17