Lull 944E-42 Service Manual - Manual (Page 436)

Hydraulic System
8.184 Model 644E-42/944E-42 Rev. 6/04
f. Main Control Valve Installation
1. Place the assembled main control valve (1) into
position on the valve plate assembly (2) aligning the
three bolt holes with the main control valve holes.
2. Insert the two long capscrews (3) and the short
capscrew (4) through the valve and tighten into the
weldnuts of the valve plate assembly. Torque all
three capscrews to 13-23 lb-ft (17-31 Nm).
3. Use new oiled o-rings as required. Reattach and
secure all hoses, clamps, etc. to the main control
valve (1).
4. Using the floor jack (5) raise the sub plate, w/valve
plate assembly (6), up into position.
5. Line up the mounting holes in the cab support (7)
and the holes in the sub plate (6). Secure in place
with the capscrews (8) and flat washers (9). Torque
the capscrews to 43-78 lb-ft (59-106 Nm).
6. Reassemble the step. Refer to Section 4.6, “Cab
Installation,” for step assembly procedures.
7. Check the routing of all hoses, wiring and tubing for
sharp bends or interference with any rotating
members, and install tie wraps and/or protective
conduit as required. Tighten all tube and hose
clamps.
8. Start the engine and run at approximately one-third
to one-half throttle for about one minute without
moving the vehicle or operating any hydraulic
functions.
9. Inspect for leaks and check the level of the hydraulic
fluid in the reservoir. Shut the engine OFF.
Note: Check for leaks and repair as required before
continuing. Add hydraulic fluid to the reservoir as
needed.
10. Wipe up any hydraulic fluid spillage in, on, near and
around the vehicle, work area and tools.
g. Main Control Valve Test
Conduct a pressure check of the hydraulic system in its
entirety. Adjust pressure(s) as required. Refer to Section
8.7, “Hydraulic System Testing.”
MU3870
1
2
3
4
MU3820
5
6
7
8
9
WARNING:
Avoid prolonged engine
operation in closed areas with inadequate
ventilation. Failure to properly ventilate exhaust
fumes can result in death or serious injury.
WARNING:
Hydraulic oil leaking under
pressure can penetrate the skin and cause
severe personal injury. DO NOT use your hand
or any part of your body to check for hydraulic
leaks. When checking for hydraulic leaks, wear
safety glasses and gloves to help provide
protection from spraying hydraulic oil. Use a
piece of cardboard or paper to search for
leaks.