Chrysler PT Cruiser Service & Repair Manual page 162

5 - 54 BRAKES - BASE
ROTOR (Continued)
Fig. 97 Minimum Brake Rotor Thickness Markings
1 - ROTOR MINIMUM THICKNESS MARKING
2 - ROTOR
Rotor thickness variation measurements should be
made in conjunction with measuring runout. Mea-
sure thickness of the brake rotor at 12 equal points
around the rotor braking surface with a micrometer
at a radius approximately 25 mm (1 inch) from edge
of rotor (Fig. 98). If thickness measurements vary
beyond the specification listed in the specifaction
table (Refer to 5 - BRAKES/HYDRAULIC/MECHAN-
ICAL/ROTOR - SPECIFICATIONS), the rotor should
be refaced or replaced. (Refer to 5 - BRAKES/HY-
DRAULIC/MECHANICAL/ROTOR
PROCEDURE)
Fig. 98 Checking Rotor Thickness
1 - MICROMETER
(Typical)
- STANDARD
ROTOR RUNOUT
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 rotor runout on the vehicle, first remove
the tire and wheel assembly. Reinstall the wheel
mounting nuts on the studs, tightening the rotor to
the hub. Mount the Dial Indicator, Special Tool
C-3339, with Mounting Adaptor, Special Tool SP-1910
on steering arm. The dial indicator plunger should
contact braking surface of rotor approximately 25
mm (1 inch) from edge of rotor (Fig. 99). Check lat-
eral runout on both sides of the rotor, marking the
low and high spots on both. Runout limits can be
found in the specification table in this section. (Refer
to 5 - BRAKES/HYDRAULIC/MECHANICAL/RO-
TOR - SPECIFICATIONS)
Fig. 99 Checking Rotor Runout
1 - SPECIAL TOOL SP-1910
2 - 25mm FROM EDGE
3 - DISC SURFACE
4 - SPECIAL TOOL C-3339
If runout is in excess of the specification, check the
lateral runout of the hub face. Before removing the
rotor from the hub, place a chalk mark across both
the rotor and the one wheel stud closest to where the
high runout measurement was taken. This way, the
original mounting spot of the rotor on the hub is
indexed (Fig. 100).
Remove the rotor from the hub.
NOTE: Clean the hub face surface before checking
runout. This provides a clean surface to get an
accurate indicator reading.
PT