Axle Assembly Repair
1600 SRM 974
7.
Make marks on the steering bearing housing and
the axle weldment for alignment during installa-
tion.
8.
If the truck has a steering gear, remove the two
capscrews and lockwashers that hold the steer
motor to the axle. Lift the steer motor and pinion
gear up and place them on the truck axle.
9.
Hold the MDU to keep it from falling. Use an
overhead crane and sling to carefully remove the
MDU. Remove the six large capscrews and lock-
washers that fasten the MDU to the axle weld-
ment. Carefully lower the MDU and tilt it to slide
it out under the lift truck frame.
NOTE: See Master Drive Unit 630 SRM 1022 to
repair the MDU.
Install
1.
Slide the MDU under the lift truck frame into the
correct position under the axle weldment. Use
an overhead crane and sling to carefully lift the
MDU into the correct position. Align the marks
made during removal, and install the capscrews
and lockwashers.
2.
If the truck has a steering chain, tighten the cap-
screws in a crisscross pattern to pull the MDU
into the axle weldment. Initially tighten the cap-
screws to 34 N•m (25 lbf ft). After all the cap-
screws have been initially tightened, tighten the
capscrews to 68 N•m (50 lbf ft).
3.
If the truck has a steering gear, tighten the cap-
screws in a crisscross pattern to pull the MDU
into the axle weldment. Initially tighten the cap-
screws to 39 N•m (29 lbf ft). After all the cap-
screws have been initially tightened, tighten the
capscrews to 78 N•m (58 lbf ft).
NOTE:
If the chain anchor came off the MDU hous-
ing, install the chain anchor at the mark made dur-
ing removal.
4.
If the truck has a steering chain, install the chain
on the motor sprocket. Install the offset link and
link pin on the chain anchor. Use a new cotter
pin to complete the assembly.
5.
If the truck has a steering gear, carefully insert
the steer motor with pinion gear into the hole.
Use a gentle back-and-forth motion to correctly
align the pinion gear to the steering gear, and
install the two capscrews and lockwashers that
hold the steer motor to the frame.
6.
Remove the fill plug and fill the MDU using the
recommended lubricant shown in the Operating
Manual or Periodic Maintenance 8000 SRM
970. The oil must go through the bearings, so add
the oil slowly and allow time for the oil to reach
the correct level. Install and tighten the fill plug.
7.
Install the traction motor. See Traction Motor,
Install.
8.
Operate the steering system to check that the
steering system is operating correctly. Check for
hydraulic leaks.
9.
Install the drive wheel on the hub of the MDU.
Tighten the wheel nuts in a crisscross pattern to
136 N•m (100 lbf ft).
HYDRAULIC STEERING MOTOR
Description
The hydraulic steering motor controls the steering
function of the master drive unit (MDU) using a
steering chain or gear. See Figure 10 and Figure 11.
The hydraulic motor rotates the MDU for steering
the lift truck.
1.
HOSE
2.
STEER MOTOR
3.
CAPSCREW
4.
LOCKWASHER
5.
SPROCKET
6.
NUT
Figure 10. Hydraulic Steering Motor,
Chain-Steered
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