Adjusting a disc handbrake

Brake drum within disc

Most cars are still fitted with drums on the back wheels with the handbrake operating directly on the brake shoes by a simple mechanical linkage .

High-quality, high-performance cars, however, often have disc brakes on the rear as well as the front wheels. With all-round disc brakes, it is very difficult to operate the rear brake pads by a mechanical linkage from the handbrake. So some manufacturers have come up with a different handbrake mechanism.

Auxiliary drum

The most common type of disc handbrake mechanism is fitted to cars such as the pre-Fiat Lancias, Jaguars, Porsches, BMWs and Volvos.

This type of handbrake consists of separate brake shoes, not pads, and works like a normal drum brake except that the drum is formed by the inner surface of the centre of the brake disc.

Cable problems

Check cable

If you are having problems with the handbrake, the first job is to check that the cable has not become frayed, seized or detached underneath the car.

Checking and adjusting the shoes

Rotate the brake disc and look through the adjustment slot to check each brake shoe in turn. If there is enough lining left, use a screwdriver to turn the star wheel adjuster until the wheel is locked. Back off the adjuster half a turn.

To adjust the cable, use the adjuster nut at the U-shaped yoke or on the primary cable or rod.

Check shoes

Having established that the cable is in good condition, you should next check the adjustment. It is best to consider handbrake adjustment on an all-disc system in two parts. First you have to adjust the brake mechanism itself and second you adjust the handbrake cable.

Find the handbrake cable adjuster and slacken it right off. Make sure that the cable seats properly where it passes through the backplate of the brake mechanism.

Then find the adjustment access slot, which is on the perimeter of the brake drum part of the disc assembly. It may have a blanking plug in it. Turn the brake disc so that you can view the handbrake shoes there should be at least ‘/gain (2mm) of lining material left.

Star wheel adjuster

Assuming the shoes are all right, look for the star wheel adjuster.

This is usually fitted at the six o’clock position. Give the star wheel adjuster and its surrounding area a squirt of penetrating oil so that it moves more easily.

Turn the star wheel adjuster with a short heavy screwdriver by resting the screwdriver on the edge of the slot and levering against the arms of the star wheel. Turn the wheel until the rear disc is locked in position and you cannot move it by hand. Then slacken off the star wheel by half a turn — you can judge this roughly by counting off four arms. Adjust the other side in the same way.

Adjust cable

Adjustment slot

In most cases the cable adjuster is under the car and is the same as that on a typical drum handbrake. The most common has the adjuster located at a U-shaped yoke.

Read more

Replacing a handbrake cable

The handbrake on most cars is a mechanical linkage of rods and cables, operated by a lever on.

Checking and renewing brake cables

Handbrake cable layouts vary from car to car, but have only a limited range of types of component.

Adjusting the brakes

A typical braking system uses disc brakes at the front of the car and drum brakes at the rear.

How ABS works

One of the most unnerving things that can happen in motoring is that you brake and one or more of.

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