Brake disc - examination, removal and refitting

Note: From 1987, thicker brake discs were fitted. If the later discs are fitted to earlier models, longer wheel studs must be fitted to accommodate the increased thickness.

Consult a dealer for further advice.

Caution: Refer to the
precautions in Section 1.

Front disc
1 Apply the handbrake, loosen the relevant roadwheel nuts, then jack up the front of the vehicle and support on axle stands (see “Jacking and Vehicle Support”). Remove the roadwheel.

2 Remove the disc caliper and carrier bracket but do not disconnect the flexible hose.

Support the caliper on an axle stand to avoid straining the flexible hose.

3 Rotate the disc and examine it for deep scoring or grooving. Light scoring is normal, but if excessive, the disc should be removed and either renewed or reground by a suitable specialist. Scrape any corrosion from the disc.

4 Using a dial gauge or a flat metal block and feeler blades, check that the disc run-out does not exceed the limit given in the Specifications. To do this, fix the measuring equipment, and rotate the disc, noting the variation in measurement as the disc is rotated. The difference between the minimum and maximum measurements recorded is known as disc run-out.

5 Mark the position of the brake disc in relation to the drive flange and on Saloon, Hatchback and Estate models, remove the retaining screw or spire washer(s), as applicable, and remove the disc. On P100 models, also mark the position of the wheel adapter plate in relation to the disc and drive flange, then unscrew the five retaining nuts and remove the wheel adapter plate and disc.

6 Refitting is a reversal of removal, but when refitting ensure that the mating faces of the disc, drive flange and on P100 models the wheel adapter plate, are clean. Align the marks made on the disc, drive flange, and where applicable the wheel adapter plate, during removal. Refit the disc caliper and carrier bracket.

Rear disc
7 Chock the front wheels, loosen the relevant roadwheel nuts, then jack up the rear of the vehicle and support on axle stands.(see “Jacking and Vehicle Support”). Remove the roadwheel and release the handbrake.

8 Detach the handbrake cable from the retaining clip on the lower arm.

9 Unscrew the two caliper carrier bracket-to-hub carrier bolts and remove the caliper assembly. Support the caliper on an axle stand to avoid straining the flexible hose.

10 Proceed as described in paragraphs 3 and 4.

11 Mark the position of the brake disc in relation to the drive flange, remove the retaining spire washer(s), and withdraw the disc.

12 Refitting is a reversal of removal, but ensure that the mating faces of the disc and drive flanges are clean, and align the marks made on the disc and drive flange during removal.

Brake drum - inspection and renewal

1 Whenever a brake drum is removed, brush out the dust, taking care not to inhale any, as it may be injurious to health.

2 Examine the internal friction surface of the drum. If deeply scored, or so worn that the drum has become ridged to the width of the shoes, then both drums must be renewed.

3 Regrinding is not recommended as the internal diameter of the drum will no longer be compatible with the shoe friction material contact diameter.

    See also:

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