1991 Ford E-350 Econoline Brake Service (ONLINE REPAIR MANUALS)

Make sure booster rubber reaction disc is properly installed as shown in Fig. , if the master cylinder pushrod is removed or accidentally pulled out. A dislodged disc may cause excessive pedal travel and extreme operation sensitivity. The disc is black compared to the silver colored valve plunger that will be exposed after pushrod and front seal are removed. The booster unit is serviced as an assembly and must be replaced if the reaction disc cannot be properly installed and aligned, or if it cannot be located within the unit itself.

• Disconnect battery ground cable.
• Disconn...

• Remove caliper and linings.
• Drain brake fluid from caliper housing, then position housing in a vise.
• Pad area between piston(s) and caliper bridge, then apply compressed air to caliper fluid port to remove piston(s). If piston is seized and cannot be forced from caliper, tap lightly around cylinder bore area while applying air pressure. Use caution when applying air pressure, as piston(s) may develop considerable force from pressure build-up.
• Remove and discard molded rubber boot(s) and square cut seal(s) from caliper assembly.
• Thoroughly clean piston(s) and caliper assembly using ...

Two warning lamps are located on the instrument panel to alert the driver to a system malfunction. The red brake warning lamp is used to indicate conventional brake system malfunctions such as low fluid level, parking brake applied and low vacuum conditions (diesel engines only). The yellow anti-lock system warning lamp is used to indicate proper warning lamp circuit operation (2 second illumination with ignition On or engine cranking). If yellow lamp comes on while vehicle is being driven, it is alerting the driver of an anti-lock system malfunction and yellow lamp can...

REMOVAL

• Raise and support vehicle.
• Remove hub cap, then wheel and tire assembly.
• On vehicles with full-floating axles, remove brake drums as follows:
• Loosen brake shoe adjustment screw.
• Remove rear axle retaining bolts and lock washers, axle shaft, and gasket.
• Remove wheel bearing locknut, lock washer, and adjusting nut.
• Remove hub and drum from axle.
• Remove brake drum-to-hub retaining screws, bolts, or bolts and nuts, then remove brake drum from hub.
• On vehicles with semi-floating axles, remove brake drums as follows:
• Remove brake drum retaining nuts.
• Remove brake drum. If brake lining is d...

Make sure booster rubber reaction disc is properly installed as shown in Fig. , if the master cylinder pushrod is removed or accidentally pulled out. A dislodged disc may cause excessive pedal travel and extreme operation sensitivity. The disc is black compared to the silver colored valve plunger that will be exposed after pushrod and front seal are removed. The booster unit is serviced as an assembly and must be replaced if the reaction disc cannot be properly installed and aligned, or if it cannot be located within the unit itself.

• Disconnect battery ground cable.
• Disconn...

SYSTEM COMPONENT LOCATIONS

Refer to system component locations, Figs. through , whenever diagnosis is required. Always disconnect the battery ground cable whenever checking resistance values within the system.

INSTRUMENTATION CHECKS

Brake System (Red) Warning Lamp

To check brake system warning lamp, turn ignition key to the Start position. The red warning lamp should glow momentarily. The warning lamp will also illuminate if the parking brake mechanism is not fully released. If warning lamp fails to glow, service of the electrical system is indicated. If warning lamp illu...