sembly require balancing. Static balancing should be
used only when two plane dynamic balancing is not
available.
For static imbalance, find location of heavy spot
causing imbalance and counterbalance wheel directly
opposite the heavy spot. Determine weight required
to counterbalance the area of imbalance. Place half
of this weight on the inner rim flange. Then place
the other half on the outer rim flange (Fig. 3). Off-
vehicle balancing is preferred.
TIRE AND WHEEL RUN OUT
Radial run out is the difference between the high
and low points on the tire or wheel periphery.
Lateral run out is the wobble of the tire or wheel.
Radial run out of more than 1.5 mm (.060 inch)
measured at the center line of the tread may cause
the vehicle to shake.
Lateral run out of more than 2.0 mm (.080 inch)
measured near the shoulder of the tire may cause the
vehicle to shake.
Sometimes radial run out can be reduced by relo-
cating the wheel and tire assembly on the mounting
studs (See Method 1). If this does not reduce run out
to an acceptable level, the tire can be rotated on the
wheel. (See Method 2).
METHOD 1 (RELOCATE WHEEL ON HUB)
Check accuracy of the wheel mounting surface;ad-
just wheel bearings.
Drive vehicle a short distance to eliminate tire flat
spotting from a parked position.
Make sure all wheel nuts are properly torqued
(Fig. 2).
Use run out gauge D-128-TR to determine run out
(Fig. 4).
Relocate wheel on the mounting, two studs over
from the original position.
Retighten wheel nuts (Fig. 2) until all are properly
torqued, to eliminate brake distortion.
Check radial run out. If still excessive, mark tire
sidewall, wheel, and stud at point of maximum run
out (Fig. 5), and proceed to Method #2.
METHOD 2 (RELOCATE TIRE ON WHEEL)
Rotating tire on wheel is particularly effective
when there is run out in both tire and wheel.
Remove tire from wheel and remount wheel on hub
in former position.
Check wheel radial run out (Fig. 6). It should be no
more than 0.9 mm (.035 inch).
Lateral run out (Fig. 6) should be no more than 1.1
mm (.045 inch).
If point of greatest wheel radial run out is near
original chalk mark, remount tire 180 degrees from
its original position. Recheck run out.
Fig. 3 Counterbalancing
Fig. 4 Run out Gauge D-128-TR
Fig. 5 Chalk Marking on Wheel, Tire, and Stud
WHEELS—TIRES 22 - 7
To Next Page
Loading...
