Lull 944E-42, Service Manual

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8.201 Model 644E-42/944E-42 Rev. 6/04
Hydraulic System
8.12.11 Power Steering Valve
The power steering valve (2) is located at the base of the
steering wheel shaft, concealed by the lower dash cover.
The valve is not serviceable and must be replaced in its
entirety if defective.
a. Power Steering Valve Removal
1. Park the vehicle on a firm, level surface, fully retract
all hydraulic cylinders, ground the attachment (if
any), place the travel select lever in the [N]
NEUTRAL DETENT position, engage the park brake
switch and shut the engine OFF.
2. Place an Accident Prevention Tag on both the
ignition switch and the steering wheel, stating that
the vehicle should not be operated. Refer to Section
1.5, “Accident Prevention Tag Usage.”
3. Unlatch and open the engine cover. Allow the
hydraulic fluid to cool.
4. To remove the power steering valve, remove both the
lower and front dash panels. Refer to Section 4.5,
“Cab Removal.”
5. Remove the power steering valve from the dash.
Refer to Section 4.3.3, “Steering Column and Valve
Replacement,” for information on removing the
steering column. The steering column and power
steering valve are mounted together. DO NOT
attempt to disassemble the steering valve.
b. Power Steering Valve Reassembly
Note: Use new oiled o-rings as required. ALWAYS
replace seals, o-rings, gaskets, etc., with new parts to
help ensure proper sealing and operation. Lubricate
seals and o-rings with clean hydraulic oil.
Note: Torque all the fittings as specified in Section 2.3,
“Torques.”
1. Transfer the fittings to the new power steering valve
(3). Note the orientation of each fitting before
removing them.
2. Transfer the elbow (4) to the “LS” port on the side of
the new power steering valve.
3. Transfer the check valve fitting (5) to the “P” port on
the front side of the new power steering valve.
4. Transfer the straight fitting (6) to the “R” port on the
front side of the new power steering valve.
5. Transfer the elbow (7) to the “T” port on the front side
of the new power steering valve.
6. Transfer the elbow (8) to the “L” port on the front side
of the new power steering valve.
WARNING:
Hot hydraulic fluid can
cause severe burns. Wait for hydraulic fluid to
cool before servicing any hydraulic component.
WARNING:
Escaping hydraulic fluid
under pressure can penetrate the skin, causing
death or serious injury. Relieve hydraulic
pressure before servicing any hydraulic
component.
MU3170
2
MU3250
3
4
5
6
7
8