MCi Crusader II 1989 Maintenance Manual page 9

Date
1-1-89
Page 1-3
MC-9 MAINTENANCE MANUAL
1. -Remove tires and wheels from axle. See Section 15.
2. Exhaust air pressure from the suspension air tank by
opening the drain cock at the bottom of the air filter.
3. Disconnect the height control valve link, and pull down on
height control valve arm to exhaust air from the front inner
beams.
4. Disconnect the hose from the front brake chambers.
5. Disconnect the steering drag link.
6. Disconnect both ends of all radius rods as outlined in this
section under Radius Rods.
7. Remove nuts from all bolts attaching air springs to the
bracket assel"[lblies.
8. Remove shock absorbers as outlined in this section under
Shock Absorbers.
9. Lower the axle assembly on jacks until air spring bead
ring bolts are cleared of the suspension supports. The axle can
now be carefully removed from under the vehicle.
Reinstallation of the axle assembly is the reverse of removal.
Make sure that air springs mounting pads on axle towers are
-:lean.
FRONT AXLE REMOVAL (Effective with Unit 41089)
To remove the entire front axle assembly first block the rear
wheels to prevent the vehicle from rolling. Raise the front end of
the coach with jacks until the bottom of the coach body is
approximately 18" (457.2 mm) from the floor. Block the body in
this position as ir:idicated in Section 3 under Coach Jacking
Points.
CAUTION: Do not raise the body in such a
way that the entire weight of the front axle
will hang on the suspension bellows assem-
blies. Damage to the air springs may result.
1. Remove tires and wheels as detailed in Section 15.
2. Exhaust air pressure from the suspension air tank by
opening drain tank at bottom of ,he air filter.
3. Disconnect the height control valve link, and pull down on
the height control valve arm to exhaust air from the front inner
beams.
4. Disconnect the hose from the front brake chambers.
5. Disconnect the steering drag link.
6. Disconnect both ends of all radius rods as outlined in this
section under Radius Rods.
7. Remove nuts from all bolts attaching
a,r
spririgs lower
bead rings to the axle tower.
8. Remove shock absorbers as outline-din this section under
Shock Absorbers.
iit.- ••
9. Lower the axle assembly on Jacks until air spring bead
ring bolts are cleared of the suspension supports. The axle can
now be carefully removed from under the vehicle.
Reinstallation of the axle assembly is the reverse c,f removal.
Make sure that air springs mounting pads on axi•e towers are
clean.
STRAIGHTENING AXLE CENTER - Before Unit 41089
The earlier MC-9 front axle center is a steel forging, heat
treated for strength and resistance to bending and torsional
strain. If the center is bent or twisted less than approximately 5
degrees from the original shape, it may be straightened. How-
ever. it is recommended that this work be done only by mechan-
ics who are thoroughly familiar with such operations and where
the proper facilities are available. Parts whjch are distorted
more than approximately 5 degrees from the original shape
must be replaced, since such distortion exceeds the elastic limit
of the material causing fractures which may result in failure
under ordinary operating conditions.
CAUTION: Do not attempt to straighten
front axles with tubular style axle centers.
Never apply heat to a front axle forging.
Front axle should be straightened cold
only.
STEERING KNUCKLE
DESCRIPTION
Later MC-9 coaches have front axles
w:!h
straight knuckle
pins. The earlier MC-9 models have axles with tapered knuckle