Maverick and Comet Repair
BRAKES - HYDRAULIC SYSTEM
All
Mavericks and Comets utilize a dual hydraulic brake circuit in
accordance with Federal safety regulations. Each circuit is
independent of the other, incorporating a tandem master cylinder, a
pressure differential warning valve, and, on disc brake models, a
proportioning valve. One circuit services the front brakes (rear of
master cylinder) and the other, the rear brakes (front of master
cylinder). In case of a leak or other hydraulic failure, 1/2 braking
efficiency will be maintained. A brake system failure will
decentralize the pressure differential warning valve, actuating a
warning light on the dash. A proportioning valve located between the
rear brake system inlet and outlet ports in the pressure
differential warning valve serves to regulate the rear brake
hydraulic pressure on disc brake models to prevent premature rear
wheel lockup during hard braking.
In normal operation, the hydraulic system
functions as follows:
When the brake pedal is depressed, the
master cylinder pistons move forward, displacing the brake fluid.
Due to the fact that the fluid volume is constant, the displacement
results in increased hydraulic pressure. This pressure is exerted
upon the wheel cylinders and/or caliper pistons, thus forcing the
brake shoes or friction pads against the drums or discs.
When the brake pedal is released, hydraulic pressure drops. On drum brakes, the brake return springs, and on disc brakes, the wobbling action of the disc returns the shoes or disc pads to their retracted positions and force the displaced fluid back into the master cylinder. On disc brakes, in addition to the wobbling action of the disc, the piston seals retracting from their stretched position help return the disc pads to their released position.