1994 Mercury Grand Marquis Brake Service (ONLINE REPAIR MANUALS)

On vehicles equipped with anti-lock brakes refer to appropriate "Anti-Lock Brakes".

POWER BOOSTER, REPLACE

CROWN VICTORIA, GRAND MARQUIS, TEMPO & TOPAZ

• Disconnect battery ground cable.
• Disconnect master cylinder from booster and position aside. It is not necessary to disconnect brake lines, but care should be taken to avoid twisting or kinking lines.
• Disconnect manifold vacuum hose from booster check valve.
• Working under instrument panel, disconnect stop lamp switch electrical connector under instrument panel.
• Remove stop lamp switch retaining pin. Slide switch off brake pedal p...

Whenever new brake components are installed in the hydraulic system, it is recommended that the entire hydraulic system be thoroughly flushed with clean brake fluid.

It may sometime become necessary to flush out the system due to the presence of mineral oil, kerosene, gasoline, etc., which will cause swelling of rubber piston cups and valves so they become inoperative. The procedure is as follows:

Flushing is...

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.

If the caliper is cracked or fluid leakage through the casting is evident, it must be replaced as a unit.

Should it become necessary to remove the caliper when installing new parts, clean all parts in alcohol, then wipe dry using lint-free cloths. Using an air hose, blow out drilled passages and bores. Check dust boots for punctures or tears. If punctures or tears are evident, install new boots during assembly.

In...

Disc brake service is extremely critical due to the close tolerances required in machining the brake disc to ensure proper brake operation.

Maintaining close control of the shape of the rubbing surfaces is necessary to prevent brake roughness. In addition, the surface finish must be non-directional and maintained at a micro-inch finish. This is necessary to avoid pulls and erratic performance and promote long lining life and equal lining wear of both the left and right brakes.

Do not attempt to refinish the rubbing surfaces unless precision equipment, ca...

Pressure bleeding is recommended for all hydraulic disc brake systems.

The disc brake hydraulic system can be bled manually or with pressure bleeding equipment. The brake pedal will require more pumping and frequent checking of fluid level in master cylinder during bleeding operation.

Do not use brake fluid drained from the hydraulic system when bleeding the brakes. Be sure the disc brake pistons are returned to their normal positions and the shoe and lining assemblies are properly seated. Before driving the vehicle, check brake operation to be sure a firm pedal has been obtain...