Chrysler 1998 Voyager Service Manual page 96

5 - 14 BRAKES
DIAGNOSIS AND TESTING (Continued)
ADJUSTER REAR DRUM BRAKE (AUTOMATIC)
The rear drum brakes on this vehicle automatically
adjust, when required, during the normal operation
of the vehicle every time the brakes are applied. Use
the following procedure to test the operation of the
automatic adjuster.
Place the vehicle on a hoist with a helper in the
driver's seat to apply the brakes. Remove the access
plug from the adjustment hole in each brake support
plate to provide visual access of the brake adjuster
star wheel.
Remove the park brake cable, for the wheel of the
vehicle that is being worked on, from the park brake
cable equalizer (Fig. 12). This is required to gain
access to the star wheel. If the cable is not removed
from the equalizer, the cable and spring inside of the
brake drum is in the way of the star wheel.
Fig. 12 Park Brake Cable Equlizer
To eliminate the condition where maximum adjust-
ment of the rear brake shoes, does not allow the
automatic adjuster to operate when tested, back the
star wheel off approximately 30 notches. It will be
necessary to hold the adjuster lever away from the
star wheel to permit this adjustment.
Have the helper apply the brakes. Upon applica-
tion of the brake pedal, the adjuster lever lever
should move down, turning the adjuster star wheel.
Thus, a definite rotation of the adjuster star wheel
can be observed if the automatic adjuster is working
properly. If one or more adjusters do not function
properly, the respective drum must be removed for
adjuster servicing.
BRAKE ROTOR
Any servicing of the rotor requires extreme care to
maintain the rotor to within service tolerances to
ensure proper brake action.
Before refinishing or refacing a rotor, the rotor
should be checked and inspected for the following
conditions:
Braking surface scoring, rust, impregnation of lin-
ing material and worn ridges.
Excessive rotor lateral runout or wobble.
Thickness variation in braking surface of the rotor
(Parallelism).
Dishing or distortion in braking surface of the
rotor (Flatness).
If a vehicle has not been driven for a period of
time, the rotors will rust in the area not covered by
the brake lining and cause noise and chatter when
the brakes are applied.
Excessive wear and scoring of the rotor can cause
temporary improper lining contact if ridges are not
removed from braking surface of rotor before instal-
lation of new brake shoe assemblies.
Some discoloration and/or wear of the rotor surface
is normal and does not require resurfacing when lin-
ings are replaced.
Excessive runout or wobble in a rotor can increase
pedal travel due to piston knock-back. This will also
increase guide pin bushing wear due to the tendency
of the caliper to follow rotor wobble.
Thickness variation in a rotor can also result in
pedal pulsation, chatter and surge due to variation in
brake output. This can also be caused by excessive
runout in the rotor and/or the hub.
Dishing or distortion can be caused by extreme
heat and abuse of the brakes.
CHECKING ROTOR FOR RUNOUT AND
THICKNESS
NOTE: The procedure for checking rotor runout
and thickness is the same for the front and rear
rotor. If there is a specification difference between
the front and rear rotor it will be designated as
such in the specifications of the following proce-
dure.
On-vehicle rotor runout is the combination of the
individual runout of the hub face and the runout of
the rotor. (The hub and rotor runouts are separable).
To measure runout on the vehicle, remove the wheel
and reinstall the lug nuts tightening the rotor to the
hub. Mount Dial Indicator, Special Tool C-3339 with
Mounting Adaptor, Special Tool SP- 1910 on steering
arm. Dial indicator plunger should contact braking
surface of rotor approximately 10 mm (0.393 in.)
from outer edge of rotor (Fig. 13). Check lateral
runout on both sides of rotor. Lateral runout of the
rotor should not exceed 0.13 mm (0.005 inch).
If lateral runout is in excess of the specification,
check the lateral runout of the hub face. Before
removing rotor from hub, make a chalk mark across
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