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12.5. Survey, removal and installation of a brake disk

This procedure belongs both to forward, and to back to brake disks. Brake disks always should be replaced or repaired in couples (both lobbies or both back disks), even in case only one of them is damaged.

Survey

 PERFORMANCE ORDER

  1. Release bolts of fastening of wheels, the car and reliably establish to a poddomkratta it on axial support. Remove a wheel and spread three bolts to hold a disk on the place. If you work with a back brake disk, release the parking brake.
  1. Remove a brake support as it is described in the Section Removal, capital repairs and installation of a support of the disk brake mechanism. To disconnect a brake hose there is no need. Having removed a support, suspend it on a piece of a wire aside that it did not prevent work. Remove a basic bracket of a support.
  1. Survey a disk surface on existence of scratches, cracks and other damages. Slight scratches and superficial flutes are admissible and usually do not influence work of brakes, but deep scratches demand removal and replacement of a disk, or if it is possible, the pro-point which is carried out by the expert in auto repair shop. In the presence of cracks the disk has to be replaced. Do not forget to examine both parties of a disk.
  1. If in operating time of brakes strong vibrations were noticed, then existence of deformation of a disk (an excessive beating) is possible. If the car is equipped with the ABS system, do not mix the vibration caused by deformation of a disk with normal work of ABS. During the work of this system usually there is a small vibration in a brake pedal.
  1. To measure a disk beating, install the dial indicator in the point located approximately in 13 mm from the outer edge of a disk. Install the indicator in zero situation and rotate a disk. Indications of the indicator should not exceed the limit set in the Size table and adjusting data at the end of the Management.
  1. If all of them exceed the established value (and if the beating does not occur owing to wear of the wheel bearing), the disk should be replaced, or if it is possible, to pierce in auto repair shop.

It is recommended to pierce disks irrespective of indications of the indicator to achieve a smooth, flat surface that, in turn, will help to avoid the vibrations of a pedal of a brake and other undesirable symptoms connected with work of disks. In case all of you decided not to pierce disks, remove at least luster from their surface by means of a skin or an emery paper, using roundabouts.

  1. It is very important to track that after a pro-point thickness of a disk did not become less extreme value, specified in the Size table and adjusting data at the end of the Management. Minimum admissible thickness of a disk is beaten out on a disk nave. Thickness of a disk can be measured by a micrometer.

Removal

 PERFORMANCE ORDER

  1. Give the screw of fastening of a disk...

... also remove a disk from a nave.

  1. If the disk "stuck" to a nave, inject plentiful amount of oil into the area between a nave and a disk and leave for several minutes to soften a rust between two components.
  1. If the back disk nevertheless does not separate, insert the thin flat screw-driver through a nave flange opening, turn an asterisk on the adjusting screw of the parking brake and squeeze boots of the parking brake.

If "stuck" a forward disk, then on some disks there is an opportunity to insert two-three bolts into special openings and to tighten them. Turn bolts in turn on couple of turns for once until the disk is released.

Installation

 PERFORMANCE ORDER

  1. Before installation make sure that a disk absolutely pure. If for removal of a disk oil was used, make sure that on it there is no its trace left. Establish a disk on a nave and spread the fixing screw of a disk. Tighten it with the required effort.
  2. Establish a basic bracket of a support (if it was removed), brake shoes and a support (see the Sections Replacement of Blocks of Disk Brake Mechanisms and Removal, capital repairs and installation of a support of the disk brake mechanism). Tighten all fasteners with the required effort.
  3. Establish a wheel, then lower the car on the earth. Squeeze out a brake pedal several times to bring brake shoes into contact with a disk.
  4. If necessary adjust boots of the parking brake (Section Adjustment of the Parking Brake).
  5. Carefully check work of brakes before normal operation of the car.