1991 Ford Escort Brake Service (ONLINE REPAIR MANUALS)

DISASSEMBLY

Except Capri, Festiva, Tracer, Scorpio, XR4Ti, Probe & 1991 Escort

• Remove caliper assembly from vehicle as described under "Caliper, Replace."
• Position fiber block and shop towels between caliper piston and caliper housing, then apply compressed air to caliper brake line fitting bore to force piston from caliper.
• Remove dust boot from caliper assembly,Figs. and .
• Remove piston seal from cylinder and discard.

Festiva

• Remove brake pads and caliper as outlined previously.
• Remove bleeder screw, drain remaining fluid from caliper, then reinstall screw.
• Remove dust boot retaining r...

Pressure bleeding is recommended for all hydraulic brake systems.

The bleeding operation itself is fairly well standardized. First step in all cases is cleaning the dirt from the filler cap before removing it from the master cylinder. This should be done thoroughly.

Pressure bleeding is fastest because the master cylinder doesn't have to be refilled several times, and the job can be done by one man. To prevent air from the pressure tank getting into the lines, do not shake the tank while air is being added to the tank or after it has been pressurized. Set the tank in the required ...

BRAKE DRUMS

Any time the brake drums are removed for brake service, the braking surface diameter should be checked with a suitable brake drum micrometer at several points to determine if they are within the safe oversize limit stamped on the brake drum outer surface. If the braking surface diameter exceeds specifications, the drum must be replaced. If the braking surface diameter is within specifications, drums should be cleaned and inspected for cracks, scores, deep grooves, taper, out of round and heat spotting. If drums are cracked or heat spotted, they must be replaced. Mi...

FRONT & REAR SPLIT SYSTEMS

When the brake pedal is depressed, both the primary (front brake) and the secondary (rear brake) master cylinder pistons are moved simultaneously to exert hydraulic fluid pressure on their respective independent hydraulic systems. The fluid displacement of the two master cylinders is proportioned to fulfill the requirements of each of the two independent hydraulic brake systems,Figs. and .

If a failure of a rear (secondary) brake system should occur, initial brake pedal movement causes the unrestricted secondary piston to bottom in the mas...

DESCRIPTION

These units are of the vacuum suspended type. Some units are of the single diaphragm type,Fig. while others are of the tandem diaphragm type,Fig. . Both single piston and double piston or split system type master cylinders are used.

The vacuum suspended diaphragm type units utilize engine manifold vacuum and atmospheric pressure for its power. It consists of three basic elements combined into a single power unit. The three basic elements of the single diaphragm type are:

• A vacuum power section which includes a front and rear shell, a power diaphragm...

The vacuum assist diaphragm assembly multiplies the force exerted on the master cylinder piston in order to increase the hydraulic pressure delivered to the wheel cylinders while decreasing the effort necessary to obtain acceptable stopping performance.

Vacuum assist units get their energy by opposing engine vacuum to atmospheric pressure. A piston, cylinder and flexible diaphragm utilize this energy to provide brake assistance. The diaphragm is balanced with engine vacuum until the brake pedal is de...