It’s all in the “feel” as you turn the wheel and move the adjuster or eccentric cam.

The process was to tighten the adjuster or eccentric adjusting cam to a point where the shoes contact the drum friction surface and backing off the adjuster or eccentric adjusting cam to where the shoes just cleared the drum. It took a good “sense of feel” to adjust the brakes evenly. The dual-servo drum brake with leading and trailing shoes requires a wrench to adjust the eccentric adjusting cams located on the backing plate. Adjustments were made by manually turning the notched wheel on the adjuster with a brake spoon for the self-energizing type. It also required more fluid in the wheel cylinder to apply the brakes. This was commonly referred to as low pedal.Īdjusting the brakes would move the shoes closer the drum friction surface and reduce the travel of the wheel cylinder piston. This caused the brake pedal to move closer to the floorboard when the brakes were applied. The return springs would retract the wheel cylinder piston to its rest position. As the linings wore, the piston in the wheel cylinder would have to travel further to engage the shoe with the drum friction surface. Before 1955, drum brakes required periodic adjustment.

In some cases, the master cylinder may contain residual check valves to prevent air from being drawn past the wheel cylinder cup seals when the shoes are retracted by the return springs. There is no compensation for lining wear. The shoes return to a fully retracted or rest position when the master cylinder releases pressure to the wheel cylinder. Drum brakes have return springs to return the shoes to a rest position and hardware to hold the shoes to the backing plate. Opposing piston calipers are bolted to the knuckle and have pins to position the pads.

78 capri slotted rotors