1997 Cadillac Catera Brake Service (ONLINE REPAIR MANUALS)

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...

AC-Delco Tandem Diaphragm Type

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 .

In normal operating mode, with service brakes in released position, the booster operates with vacuum on both sides of its diaphragms. When brakes are applied, air at atmospheric pressure is admitted to one side of each diaphragm to provide power assist. When the service brake is released, atmospheric air is shut off from one side of each diaphragm. The a...

Replace

• Remove approximately ^2/3 of brake fluid from master cylinder.
• Raise and support front of vehicle, then remove wheel and tire assembly.
• Using suitable C-clamp, push piston back into caliper bore, Fig. .
• 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 to be replaced, do not disconnect brake line fitting fr...

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

Replace

• Remove brake pads as outlined under "Brake Pad Service," then the rear caliper pipe, Fig. .
• Remove rear brake caliper bolts, then the caliper from rotor.
• Reverse procedure to install, noting the following:
• Torque rear brake caliper bolts to 59 ft. lbs.
• Torque brake pipe fitting to 12 ft. lbs.

Disassemble

• Install piston retainer tool No. J 22429, or equivalent, on opposite cylinder to be removed.
• Remove piston by directing dry filtered compressed air into fluid channel port of caliper housing, then cover exposed bore with tool No. J 22429, or equivalent, and rem...