Broderson IC-280-A, Accompaniment To The Installation, Operation And Maintenance Manual

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MECHANICAL ADJUSTMENTS
FASTENERS:
All fasteners on the IC-280 should be checked and retightened, if required, as a part of the pre-
ventive maintenance program. Particular attention should be given to the drive axle mounting
bolts, pump mounting bolts, pump drive shaft bolts, rotation bearing bolts, rotation gearbox
bolts, and winch bolts. All bolts used in assembly are heat-treated
Grade 5 or 8 . Torque the
wheel nuts to 500 foot-pounds (680 Nm). BMC has two types of fasteners that may be used in
the rotation bearing, depending on when the machine was assembled. Torque the rotation
bearing fasteners as shown below.
Top locking nuts can be identified by the
curved top surface. Torque the rotation
bearing mounting bolts to 700 foot-pounds
(950 Nm) while holding the nuts stationary –
or torque the nuts to 550 foot-pounds (750
Nm) while holding the bolts stationary. Grade 9 hex nuts can be identified by the
flat top surface. Torque the rotation bearing
mounting bolts to 625 foot-pounds (850 Nm)
while holding the nuts stationary – or torque
the nuts to 625 foot-pounds (850 Nm) while
holding the bolts stationary.
ROTATION GEARBOX:
The rotation gearbox assembly is attached to the chassis top plate by four cap screws. It is held
in proper engagement with the external teeth on the bull gear by two setscrews. It is further re-
strained from torsional movement by two bolts on each side of the gearbox mounting flange.
The gearbox should be adjusted with the boom centered over the front of the chassis. This cen-
ters the gearbox pinion on the “high side” of the bearing gear teeth. Adjust the gearbox inward
until there is light contact between pinion and bull gear teeth. Retighten the four mounting bolts
and the four side bolts.
TRANSMISSION AND AXLE TROUBLESHOOTING AND OVERHAUL:
Procedures for transmission and axle troubleshooting and overhaul are beyond the scope of the
BMC Maintenance and Parts Manuals. International Transmission Ltd. factory service manuals
are available from BMC as follows:
Transmission Service Manual, BMC Part Number 990-00021
Axle Service Manual, BMC Part Number 990-00020