Wheel Balance - Fiat 850 Sedan 1968 Shop Manual

184
Uneven Tire Wear (continued).
POSSIBLE CAUSES
FIAT - 850 PASSENGER CARS
REMEDIES
13) Underlnflated tires: wear Is particularly remark-
able on two sides ,ather than in the center of
tire tread.
14) Overinflated tl,es: excessive wear on tire tread
center portion.
15) Low front wheel toe-in: excessive wear on inne,
sides of tire tread.
16) High front wheel toe-in: excessive wear on outer
sides of tire tread.
11) Steering system out of adjustment and con-
sequent high toe-in on one wheel and low toe-in
on the other. Wear is particularly remarkable on
tread inner side of one tire and oule, side of the
other.
Pull to One Side.
POSSIBLE CAUSES
1) Front wheels out of balance.
2) Uneven front tire pressure.
3) Excessive wear difference in one pair of tires.
Wheel Balance.
The balance of a wheel and tire assembly is
an important factor which must be accurately looked
after for safe and comfortable drive.
As a matter of fact unbalanced wheels may bring
about abnormal wear in running gear and, mainly.
in tires.
The conditions which are apt to adversely affect
wheel balance are the following:
a) wheel run-out from warpage or impact;
b) wheel out-of-round caused by irregularities
in the rim or tire;
c) static unbalance or uneven distribution of
the weight around the axis of rotation.
Conditions a) and b) may be easily detected:
13) Inflate tires to recommended values.
14) Reduce pressure to recommended values.
15) Check and adjust toe-in.
16) Check and adjust toe-in.
17) Set front end geometry and check steering and suspension
components for distortion.
REMEOIES
1) Balance wheels.
2) Check pressures and set them to recommended value.
3) Replace tire which is exceedingly worn.
first rotate the rim alone and then the wheel and
tire and:
- using a scriber check wheel inside flanges
retaining the tire bead and the
rim
well for run-out
in
excess of
.0394" (1
nun);
- when installing tires, see to it that the red
spot is situated at the valve.
To correct run-out of wheel rim take down tire
and straighten wheel rim using an arbor press.
To correct the condition c), balance the wheels
using electronic balancer Ap. 5029.
Thanks to this device best and quick results are
obtained allowing to determine the amount of weights
and their location on rims for correct wheel balance.
For the use of balancer
1
adhere to the directions
in the handbook delivered with each machine.