Warner Electric Wheel-Brakes (Std) - Manual (Page 15)

15 Warner Electric • 800-825-9050 819-0514
Check For Loose Wheel Bearings
During brake inspection periods and before removing
wheels, jack up each wheel and check for loose wheel
bearings (Figure 3-6). If by using a bar under the tires,
the wheels can be moved up and down on the axle the
wheel bearings are loose or worn. This condition can
cause grabby or noisy brakes, a dragging brake which
creates undue heat and rapid lining wear, or a possible
wheel lockup. Bearings Must Be Kept Snug.
Figure 3-6
Checking for Loose Wheel Bearings
When wheels must be removed for maintenance or
repair, always check for worn or defective bearings and
cups (Figure 3-7). Defective parts must be replaced.
Also check the hub for cracks and for proper fit of the
bearing cups in the hub.
Figure 3-7
Inspecting Wheel Bearings
Inspect Drums
Before relining brakes or during regular maintenance
periods, the drum should be checked for an
out-of-round condition. This may be accomplished
by an inside micrometer or a dial indicator mounted
on a stub spindle (Figure 3-8). Drums should not be
out-of-round more than .010”, since such a condition
can cause erratic, grabby brakes and possible difficulty
in assembling the wheel onto the axle.
Whenever a wheel is removed, always check the drum
mounting bolts. They must be kept tight, since a loose
drum has the same effect as loose wheel bearings. A
loose drum may also cause the drum mounting bolts to
shear off during a brake application.
Figure 3-8
Checking Drum with Inside Micrometer
and Dial Indicator