1990 Chevrolet Cavalier Brake Service (ONLINE REPAIR MANUALS)

The rear drum brakes have self-adjusting shoe mechanisms that assure correct lining-to-drum clearances at all times. The automatic adjusters operate only when the service brakes are applied.

Although the brakes are self-adjusting, an initial adjustment is necessary after the brake shoes have been replaced, or when the length of the star wheel adjuster has been changed during some other service operation.

SERVICE BRAKE, ADJUSTMENT

• Raise and support vehicle, then remove rear wheels and brake drums.
• Check to make sure parking brake cable linkage and levers on secondary brake shoe are...

Remove wheels and inspect brake disc, caliper and linings. The wheel bearings should be inspected at this time and repacked if necessary. Do not get any grease on the linings.

Do not replace individual pads or replace pads on one wheel of an axle set alone, as braking performance will be adversely affected.

If a visual inspection does not ade...

COMPOSITE TYPE

Refer toFigs. and when performing the following procedures.

EXCEPT CORVETTE

Disassembly

• Remove master cylinder from vehicle as follows:
• Disconnect and plug hydraulic lines.
• Remove two master cylinder attaching nuts, then the master cylinder.
• Remove reservoir cover and diaphragm. Discard old brake fluid in reservoir.
• Inspect cover and diaphragm. Replace if cut, cracked or deformed.
• Remove fluid level switch, if equipped.
• On models with compact master cylinder, remove proportioner valve assembly,Fig. .
• Depress primary piston and remove lock ring.
• Plug primary fluid ou...

DESCRIPTION

This unit utilizes a vacuum power chamber, consisting of a front and rear shell, housing divider, front and rear diaphragm, plate assemblies, hydraulic pushrod and a diaphragm return spring,Figs. and .

The unit operates in much the same manner as the single diaphragm unit described previously. The diaphragm and plate assemblies utilize the pressure differential between the engine intake manifold vacuum and atmospheric pressure to assist in braking.

TROUBLESHOOTING

Hard Pedal

• Internal vacuum leak.
• Faulty control valve.

Brakes Grab

• Faulty control valve...

CALIPER REMOVAL

• Remove approximately^2/3 of brake fluid from master cylinder.
• Raise and support front of vehicle, then remove wheel and tire assembly.
• Position suitable pliers over inboard pad and housing as shown in Fig. , and squeeze pliers to compress caliper piston.
• If caliper assembly is being removed for service, 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 t...

When working on or around brake assemblies, care must be taken to prevent breathing asbestos dust, as many manufacturers incorporate asbestos fibers in the production of brake linings. During routine service operations the amount of asbestos dust from brake lining wear is at a low level due to a chemical breakdown during use, and a few precautions will minimize exposure.

• Do not sand or grind brake linings unless suitable local exhaust ventilation equipment is used to prevent excessive asbestos exposure.
• Wear a suitable respirator approved for asbestos dust use during all repai...