PREVOST X3-45 Multiplex, Руководство по обслуживанию

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Section 10: FRONT AXLE
PA1562
5
6. FRONT WHEEL ALIGNMENT
Correct front wheel alignment must be maintained
for steering comfort and satisfactory tire life. Road
shocks and vibrations, as well as normal stress
and strains on the front-end system can, under
normal operating conditions, result in loss of front
wheel alignment.
Check the front wheel alignment when the
following occurs:
1. Every 200,000 miles (320 000 km) or 24
months (normal maintenance);
2. When the vehicle does not steer correctly; or
3. To correct a tire wear condition.
There are two types of front wheel alignment:
minor alignment and major alignment .
6.1 MINOR FRONT WHEEL ALIGNMENT
Perform a minor front wheel alignment for all
normal maintenance conditions.
Perform the minor front wheel alignment in the
following sequence :
1. Inspect all the systems that affect the wheel
alignment. See paragraph 6.3, ‘’Inspection
Before Alignment’’ in this section.
2. Check the hub bearings. See section 13,
‘’Wheels, hubs and Tires’’ under heading 8:
Front and Tag Axle Wheel Hubs.
3. Check and adjust the toe-in.
6.2 MAJOR FRONT WHEEL ALIGNMENT
Perform a major front wheel alignment to correct
steering and tire wear conditions.
Perform the major front wheel alignment in the
following sequence:
1. Inspect all systems affecting the wheel
alignment. See paragraph 6.3, ‘’Inspection
Before Alignment’’ in this section.
2. Check the hub bearings. See section 13,
‘’Wheels, hubs and Tires’’ under heading 8:
Front and Tag Axle Wheel Hubs.
NOTE
If steering angle stoppers are changed, a
special procedure is required for readjusting
gearbox steering limiter. See paragraph 6.5
‘’Hydraulic Stop’’ in this section.
3. Check and adjust the turning angle
adjustment.
4. Check the camber angle.
5. Check and adjust the caster angle.
6. Check and adjust the toe-in.
6.3 INSPECTION BEFORE ALIGNMENT
Check the following before doing a front wheel
alignment:
1. Ensure that the vehicle is at normal riding
height. See Section 16, ‘’Suspension’’
under heading 7: ‘’Suspension Height
Adjustment’’ .
2. Ensure that front wheels are not the cause
of the problem. See Section 13, ‘’Wheels,
Hubs and Tires’’ . Inspect the tires for wear
patterns indicating suspension damage or
misalignment.
a. Make sure the tires are inflated to
the specified pressure.
b. Make sure the front tires are the
same size and type.
c. Make sure the wheels are balanced.
d. Check wheel installation and
straightness.
3. Check the wheel bearing adjustment.
4. Check steering linkage for bending and
pivot points for looseness.
5. Check knuckle pins for evidence of
excessive wear.
6. Check radius rods for bending and rubber
bushings for evidence of excessive wear.
7. Make sure all fasteners are tightened to the
specified torque. Use a torque wrench for
verification. As soon as the fastener starts
to move, record the torque. Correct if
necessary. Replace any worn or damaged
fasteners.
6.4 TURNING ANGLE ADJUSTMENT
The maximum turning angle is set through the
two steering stop screws installed on the axle
center. The turning angle is factory adjusted to
accommodate the chassis design, and
therefore, does not require adjustment on new
vehicles. However, it should be checked and