1991 Mercury Colony Park Brake Service (ONLINE REPAIR MANUALS)

• Remove wheel, drum and brake shoes.
• Disconnect hydraulic line at wheel cylinder. Do not pull metal line away from cylinder as the cylinder connection will bend metal line and make installation difficult. Line will separate from cylinder when cylinder is moved away from brake backing plate.
• Remove screws holding cylinder to brake plate and remove cylinder.

OVERHAUL

• Referring toFig. as a guide, remove boots, pistons, springs and cups from cylinder.
• Place all parts, except cylinder casting in clean brake fluid. Wipe cylinder walls with clean brake fluid.
• Examine cylinder bore. A scored ...

• Raise and support rear of vehicle, then remove tire and wheel assembly.
• Remove brake drum. If brake lining is dragging on brake drum, back off brake adjustment by rotating adjustment screw. Refer to individual car chapter for procedure.If brake drum is rusted or corroded to axle flange and cannot be removed, lightly tap axle flange to drum mounting surface with a suitable hammer.
• Install suitable wheel cylinder clamp over ends of wheel cylinder to retain pistons in bore.
• On type 1 brakes,Fig. , remove parking brake lever retaining clip.
• On both types,Figs. and , remove adjuster leve...

BENDIX, TEVES & DOUBLE DIAPHRAGM BOOSTER

On Bendix, Teves and Double Diaphragm Booster type power brake units, overhaul is not required. If it has been determined that the brake booster is defective, replace power brake unit as an assembly. In some instances, the only service required is replacement of the check valve and grommet and pushrod adjustment.

SINGLE DIAPHRAGM BOOSTER

Disassembly

• Remove brake booster from vehicle.
• Place front shell of booster in a vise.
• Remove clevis from valve rod and plunger assembly.
• Remove dust boot from rear shell,Fig. , then place alignment marks on fron...

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...

REMOVAL

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

• Remove brake fluid until reservoir is half full.
• Raise and support front of vehicle, then remove wheel and tire assembly.
• Remove caliper locating pins.
• Lift caliper assembly from adapter plate, then remove outer shoe from caliper assembly.On some models, slip shoe down caliper leg until clip is disengaged.
• Remove inner shoe and lining assembly.On some models, pull shoe straight out of piston. This should require a force as high as 20-30 lbs.
• Suspend caliper from inner fender housing with wire to avoid damaging brake ...

Never use copper tubing as a replacement for steel tubing. Copper tubing is subject to fatigue cracking and corrosion which could result in brake system

Steel tubing is used to conduct hydraulic pressure to the brakes. All fittings, tubing and hose should be inspected for rusted, damaged or defective flared seats. The tubing is equipped with a double flare/inverted seat or I.S.O. flare to insure more positive seating in the fitting. To repair or reflare tubing, proceed as follows:

DOUBLE FLARE/INVERTED SEAT

• Using the tool shown inFig. or equivalent, cut off the damaged seat or da...