Brake Line; Disc Rotor Machining - Jeep 1997 Grand Cherokee Service Manual

ZG
SERVICE PROCEDURES (Continued)
stem must either be pressed inward, or held outward
slightly. a spring clip tool or helper is needed to hold
the valve stem in position.
Follow the manufacturers instructions carefully
when using pressure equipment. Do not exceed the
tank manufacturers pressure recommendations. Gen-
erally, a tank pressure of 15-20 psi is sufficient for
bleeding.
Fill the bleeder tank with recommended fluid and
purge air from the tank lines before bleeding.
Do not pressure bleed without a proper master cyl-
inder adapter. The wrong adapter can lead to leak-
age, or drawing air back into the system.

DISC ROTOR MACHINING

Rotor braking surfaces can be sanded or machined
in a disc brake lathe.
The lathe must machine both sides of the rotor
simultaneously with dual (two) cutter heads (Fig.
16). Equipment capable of machining only one side at
a time will produce a tapered rotor.
The lathe should also be equipped with a grinder
attachment or dual sanding discs for final cleanup or
light refinishing (Fig. 17).
If the rotor surfaces only need minor cleanup of
rust, scale, or minor scoring, use abrasive discs to
clean up the rotor surfaces. However, when a rotor is
scored or worn, machining with cutting tools will be
required.
CAUTION: Do not machine the rotor if it will cause
the rotor to fall below minimum allowable thick-
ness.

BRAKE LINE

Mopar preformed metal brake line is recommended
and preferred for all repairs. However, double-wall
steel line can be used for emergency repair when fac-
tory replacement parts are not readily available.
Special, heavy duty tube bending and flaring
equipment is required to prepare double wall brake
line. Special bending tools are needed to avoid kink-
ing or twisting metal brake line. In addition, special
flaring tools are needed to provide the inverted-type,
double flare required on metal brake lines.
FLARING PROCEDURE
(1) Cut off damaged tube with Tubing Cutter.
(2) Ream cut edges of tubing to ensure proper
flare.
(3) Install replacement tube nut on section of tube
to be repaired.
(4) Insert tube in flaring tool. Center tube in area
between vertical posts.
(5) Place gauge form over the end of the tube.
BRAKING DISC BRAKING DISC GRINDER CUTTING TOOLS
Fig. 16 Rotor Refinishing
Fig. 17 Rotor Grinder
(6) Push tubing through flaring tool jaws until
tube contacts recessed notch in gauge that matches
tube diameter.
(7) Squeeze flaring tool jaws to lock tubing in
place.
(8) Insert plug on gauge in the tube. Then swing
compression disc over gauge and center tapered flar-
ing screw in recess of compression disc (Fig. 18).
DAMPER
BRAKES 5 - 13