1998 Cadillac Seville Brake Service (ONLINE REPAIR MANUALS)

• After disassembling a power brake unit, soak all metal parts in solvent.
• Use only alcohol on parts containing rubber. After the parts have been thoroughly cleaned and rinsed in solvent, they should be rewashed in clean alcohol before assembling.
• Use compressed air...

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.

Master Cylinder Internal Fluid Leakage Check

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 ...

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...

The caliper assembly, Fig. , has a single bore and is mounted to the support bracket with two mounting bolt and sleeve assemblies. Hydraulic pressure created by applying the brake pedal, is converted by the caliper to a stopping force. This force acts equally against the piston and the bottom of the piston bore to move the piston outward and to slide the caliper inward resulting in a clamping action. This clamping action presses the linings against the rotor, creating friction to stop the vehicle.

When the parking brake is applied, the external caliper parking brake lever moves and 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...