Broderson IC-250-3D, Operation And Maintenance Manual

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MECHANICAL ADJUSTMENTS
FASTENERS:
All fasteners on the IC-250 should be checked and retightened if required, as a part of the pre-
ventive maintenance program. Particular attention should be give 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 fur-
ther restrained from torsional movement by two bolts on each side of the gearbox mounting
flange. The gearbox should be adjusted with the boom centered over front of the chassis. This
centers the gearbox pinion on the “high side” of the bearing gear teeth. Adjust the gearbox in-
ward until there is “light contact” between pinion and bull gear teeth. Retighten the four mount-
ing 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
PARK BRAKE TEST AND ADJUSTMENT:
1. Fully apply the parking brake
2. Start the engine, retract the boom to the appropriate traveling position and raise the outrig-
gers.
3. Select fourth gear.
4. Push down hard on the foot brake pedal.
5. Select forward gear.