1993 GEO Metro Brake Service (ONLINE REPAIR MANUALS)

This single piston sliding caliper assembly, Fig. , is mounted to a support bracket by two slide pins. The caliper assembly slides on the two mounting pins. Upon brake application, fluid pressure a...

BRAKE ROUGHNESS

The most common cause of brake chatter on disc brakes is a variation in thickness of the disc. If roughness or vibration is encountered during highway operation or if pedal pulsation is experienced at low speeds, the disc may have excessive thickness variation. To check for this condition, measure the disc at 12 points with a micrometer at a radius approximately one inch from edge of disc. If thic...

• Grease or any other foreign material must be kept off the brake linings, caliper, surfaces of the disc and external surfaces of the hub, during service procedures. Handling the brake disc and caliper should be done in a way to avoid deformation of the disc and nicking or scratching brake linings.
• If inspection reveals rubber piston seals are worn or damaged, they should be replaced immediately.
• During removal and installation of a wheel assembly, exercise care so as not to interfere wi...

Two basic types of power assist mechanisms are used: vacuum assist diaphragm assemblies, which use engine vacuum or, in some cases vacuum pressure developed by an external vacuum pump. The second type is a hydraulic pressure assist mechanism, which use pressure developed by an external pump (usually the power steering pump). Both systems act to increase the force exerted on the master cylinder piston by the operator. This in turn increases the hydraulic pressure delivered to the wheel cylinders, while decreasing driver effort necessary to obtain acceptable stopping performance.

V...

CALIPER REMOVAL

• Remove approximately ^2/3 of brake fluid from master cylinder.
• Raise and support vehicle.
• Mark relationship between front wheel and axle, then remove wheel and tire assembly.
• If caliper assembly is to be serviced, remove inlet fitting attaching bolt, copper washer, and inlet fitting from caliper housing. Plug opening in inlet fitting to prevent fluid loss and contamination. Do not crimp brake hose, as this may damage internal structure of hose. If only shoe and lining assemblies are to be replaced, do not disconnect brake line fitting from caliper.
• Remove caliper mount...

REMOVAL

• Raise and support vehicle.
• Remove spindle cap by hammering lightly at 3 points around cap.
• Remove cotter pin or unfasten staked portion of nut, then remove castle nut and washer.
• Loosen parking brake cable adjusting nuts.
• Remove backing plate plug, Fig. .
• Insert screwdriver into plug hole until it contacts shoe hold-down spring and push in direction shown, Fig. . This pushes hold-down spring up and releases parking brake shoe lever from hold-down spring, resulting in added clearance between shoe and drum.
• Using slide hammer tool No. J-2619-01 and brake drum remover tool No. J-348...