Section 4 • Repair Procedures
REV A
4 - 12
AL8000HT Light Tower
Part No. 116478
September 2008
3-5
Tower Rotation Motor
How to Remove the Tower
Rotation Motor
Note: When removing a hose assembly or fitting,
the O-ring on the fitting and/or hose end must be
replaced and then torqued to specification during
installation. Refer to Section 2,
Hydraulic Hose and
Fitting Torque Specifications.
Note: Perform this procedure with the tower in the
stowed position and the transport lock pin installed.
1 Tag, disconnect and plug the tower rotation
motor hydraulic hoses. Cap the fittings on the
motor.
Bodily injury hazard. Spraying
hydraulic oil can penetrate and
burn skin. Loosen hydraulic
connections very slowly to allow
the oil pressure to dissipate
gradually. Do not allow oil to squirt
or spray.
2 Remove the rotation motor pinion gear guard
fasteners. Remove the guard.
3 Remove the rotation motor mounting fasteners.
Remove the motor from the machine.
Note: When installing a rotation motor, the gear
backlash will need to be adjusted. See
How to
Adjust the Tower Rotation Gear Backlash.
TOWER COMPONENTS
How to Adjust the Tower
Rotation Gear Backlash
The rotation motor mounting fasteners are located
in slotted holes to allow the adjustment of gear
backlash between the motor pinion gear and the
rotation bearing ring gear. Proper backlash
adjustment is critical to safe machine operation and
component service life. An improper backlash
adjustment could decrease component service life
and may result in component damage.
Note: Perform this procedure with the tower in the
stowed position and the transport lock pin installed.
1 Loosen the tower rotation motor mounting
fasteners. Do not remove them.
2 Push the rotation motor towards the rotation
bearing as far as possible (this will push the
pinion gear into the rotation bearing ring gear).
3 Loosen the lock nut on the adjustment bolt.
4 Adjust the lock nuts until there is approximately
1
/
16
inch / 1.5 mm gap between the end of the
bolt and the rotation motor case. Tighten the
lock nuts of the adjustment bolt.
5 Rotate the rotation motor away from the bearing
until it contacts the adjustment bolt. Torque the
rotation motor fasteners to specification. Refer
to Section 2,
Specifications.
6 Rotate the tower through full range of motion.
Check for tight spots and binding. Readjust if
necessary.
