1993 Cadillac Deville Brake Service (ONLINE REPAIR MANUALS)

AC-DELCO TANDEM DIAPHRAGM TYPE

OVERHAUL

Disassemble

• Remove pedal pushrod boot, silencer, check valve, vacuum switch and grommets, as equipped, then the front housing seal.
• Scribe matching marks between front and rear housing sections, then mount booster assembly in suitable holding fixture with rear housing facing up.
• Apply pressure to housing with holding fixture forcing screw and rotate rear housing counterclockwise to unlock housing halves.
• Slowly release spring tension, then remove booster assembly from holding fixture. Do not allow spring tension to release suddenly, as ...

• If any parts are of doubtful strength or quality due to heat discoloration, or are worn, replace them.
• Inspect wheel cylinder dust boots for signs of excessive wear or damage. If any leakage is apparent replace wheel cylinder.
• Clean dirt and/or rust from brake drum, backing plate and all other components. Do not use compressed air or dry brush to clean brake parts. Many brake parts contain asbestos fibers which, if inhaled, can cause serious injury. Clean brake parts with a water soaked rag or a suitable vacuum cleaner to minimize airborne dust.

BRAKE DRUMS

Any time the brake drums are r...

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...

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 repair proced...

When troubleshooting the hydraulic brake system, perform the following checks and inspections as outlined below. If problem still exists within system, refer to Fig. first, then to Figs. and as necessary.

CHECKING FOR FLUID LEAKAGE

Start engine and depress the brake pedal. If the pedal gradually falls under constant pressure, the hydraulic system may be leaking. Raise the vehicle on a lift and check all tubing lines and backing plates for signs of leakage. It may be necessary to lift or re...

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 assemblie...