12.6. Replacement of boots of drums of brake mechanisms

Boots of brake drums need to be replaced on both wheels at the same time - never replace boots only on one wheel. Besides, the dust gathering on the brake system may contain the asbestos harmful to your health. Never delete it by means of compressed air and do not inhale it. During the work with brakes it is necessary to put on the special filtering mask. Never, under no circumstances, use solvents on the basis of gasoline for washing of details of a brake. Use only a special cleaner of the brake system.

When replacing boots it is always necessary to replace the coupling and holding springs, and also thermoclips of the automatic regulator. Owing to constant change of temperatures to which springs are exposed they through a certain period of time lose the elasticity that can lead to pulling of boots to a drum, and as a result of it, to their premature wear. When replacing boots of brake mechanisms use only original details or high-quality details of recognized firms manufacturers.

All four boots of back brake mechanisms have to be replaced at the same time, but not to mix their components, work with one assembly for time. Some components of back brake mechanisms are various for the left and right side therefore try not to mix them.

If it is found out that the wheel cylinder escapes or has other malfunctions, replace it after replacement of brake boots. It becomes by a simple detachment of the hydraulic line and removal of the cylinder from a brake board, previously отболтив it. The attempt to repair the proceeding cylinder most likely will not result in satisfactory result, even in the presence of spare parts.


  1. Block forward wheels, then release bolts of fastening of back wheels, a back of the car and reliably establish to a poddomkratta it on axial support. Remove back wheels and release the parking brake.
  1. Give the screw of fastening of a drum and remove a drum.
  1. If a drum<прикипел> to a nave, inject oils between a nave and a drum.
  1. If the drum nevertheless is not removed, then it is possible that boots pierced in it grooves, and they should be parted. Insert the narrow flat screw-driver into one of openings in a flange of a nave and rotate a regulator castor until the drum is not removed from an axis.
  1. Survey a drum on existence of the cracks, scratches, deep grooves and steady spots having an appearance of the decoloured sites of a surface. If these spots cannot be removed by means of an emery cloth, or in the presence of other damages, the drum should be given to auto repair shop for a pro-point.

Professionals recommend to pierce brake drums every time during the work with brakes. The pro-point will remove possible deformation of drums. If drums are worn-out so that their deformations cannot be corrected a pro-point without excess of the sizes of the most admissible diameter specified on a drum, then it is necessary to replace them with new. If all of you decided not to pierce drums then remove gloss from their surface by means of an average emery cloth, applying rotary motions.

  1. Unhook the lower coupling spring from a forward boot.

... then unhook it from a back boot and remove.

  1. Unhook the top coupling spring from a forward boot.

... then unhook it from a back boot and remove.

  1. Remove the holding spring of a forward boot...

... and the holding spring of a back boot.

  1. Take off a forward boot.
  1. Remove assembly of the regulator. Clean the regulator and make sure that its castor freely goes on a carving. It is recommended to replace a thermo-clip (a spring clip near a regulator castor) every time when replacing boots. Establish a regulator castor so that assembly was closest to installation.
  1. Disconnect a cable of the drive of the parking brake from the lever of the parking brake and take off a back boot.
  1. Installation repeats the procedure of removal upside-down, but pay attention to the following items.
  1. Apply a layer of high-temperature brake lubricant on a brake board. Be careful that lubricant did not get on the rubbing surfaces of brake boots or drums.
  1. Make sure that assembly of the regulator correctly rose in deepening in the lever of the parking brake.
  1. At installation of the mechanism of automatic adjustment at first install the lever on a boot.

... then attach the lower end of a spring on the lever, and hook on the top end for a special opening in a forward boot.

  1. Upon termination of work assembly of the brake mechanism has to look as it is shown on a photo. Now it is possible to pass to the following brake mechanism.
  1. After completion of work with both brake mechanisms install brake drums.
  2. If the wheel cylinder was replaced (see the Remark 2), pump over hydraulic system as it is described in the Section Pumping of Hydraulic System of Brakes.
  3. Squeeze out a brake pedal several times to put the self-regulation mechanism in action. When weakening regulators from brake drums clicks will be heard.
  4. Check adjustment of the parking brake.
  5. Establish wheels and fixing bolts. Lower the car on the earth and tighten bolts of fastening of wheels with the required effort. Carefully check work of brakes before normal operation of the car.