b. Check the bearing’s outer seal (A,
Figure 5
)
for buckling or other damage that would al-
low dirt to enter the bearing.
c. Check the bearing fit in the hub by trying to
move the bearing laterally with your hand.
The bearing should be tight in the bore. Loose
bearings allow the wheel to wobble. If a bear-
ing is loose, the bearing bore in the hub is
probably worn or damaged.
4. Remove any corrosion from the axle (
Figure 6
)
or collars with a piece of fine emery cloth.
WARNING
Do not attempt to straighten a bent
axle.
5. Check axle runout by rolling the axle along a
surface plate or a piece of glass. If the axle is not
straight, replace it.
6. Install the wheel on a truing stand. Check wheel
runout as follows:
a. Measure the radial (up and down) runout of
the wheel rim with a dial indicator as shown
in
Figure 7
.
b. Measure the axial (side to side) runout of the
wheel rim with a dial indicator as shown in
Figure 7
.
7. If the wheel runout is out of specification (
Table
1
), inspect the wheel bearings as described earlier in
this section.
a. If the wheel bearings are good, the wheel
must be replaced.
b. If either wheel bearing is worn, disassemble
the hub and replace both bearings as a set.
8. Check the tightness of the brake disc bolts (C,
Figure 3
). If a bolt is loose, remove and reinstall the
bolts with medium-strength threadlocking com-
pound. Clean any old threadlocking compound
from the threads and torque the bolts to 23 N•m (17
ft.-lb.).
9. Visually inspect the brake discs and measure the
brake disc deflection as described in Chapter Thir-
teen. If deflection is excessive, measure wheel run-
out. If wheel runout is within specification, replace
the brake disc. Refer to the procedure in Chapter
Thirteen.
10. Inspect the wheel rim for dents, bending or
cracks. Check the rim and rim sealing surface (cast
wheels) for scratches that are deeper than 0.5 mm
(0.01 in.). If any of these conditions are present, re-
place the wheel.
WHEEL AND TIRES
285
10
5
6
7
WHEEL RUNOUT
Axial
runout
Radial
runout
