11:12. Service of drum brake mechanisms of back wheels

For rubbing of components of brake mechanisms it is necessary to use special means, or methyl alcohol, - at all do not apply solvents on an oil basis!

Design of the drum brake mechanism of a back wheel

1 — the Nut
2 — the Brake drum
3 — Pruzhina of the adjusting lever
4 — the Adjusting lever
5 — the Top coupling spring
6 — the Adjusting razzhimny level
7 — the Directing spring of a brake boot

8 — the Lower coupling spring
9 — the Forward boot
10 — the Bolt with the With-shaped washer
11 — the Back boot
12 — the Cable of the drive of the parking brake
13 — the Executive lever of the drive of the parking brake
14 — the Bolt
15 — Assembly of the wheel cylinder



  1. Turn off nuts of fastening of the brake drum to a half shaft flange.
  1. The screw-driver rotating the regulator through a service opening, take away boots from drum walls, then turn out the fixing screw and remove a drum.
  1. By means of nippers remove a spring of the adjusting lever.
  1. Remove the adjusting lever.
  1. Remove the top coupling spring.
  1. Having turned clockwise the regulator of a razzhimny level, remove the last.
  1. Develop an anchor finger parallel to a flute and remove the directing springs of boots.
  1. Remove the lower coupling spring.
  1. By means of nippers disconnect a driving cable from the executive lever of the parking brake.
  1. Disconnect a hydraulic hose from the back party of a brake board, then turn out couple of fixing bolts and remove the wheel cylinder.
  1. In case of need disassemble the wheel cylinder on components (two boots, two pistons, two piston cups, a razzhimny spring).

Assessment of a condition of components


  1. Carefully smooth out all removed components and attentively study their general state. Replace defective parts.
  1. Define degree of wear of frictional overlays of boots, in case of need make replacement.

Boots should be replaced in a set for both wheels of a back axis!

  1. Check the working surface of reels for existence of signs of an overheat, cracks, zadir and other mechanical damages. Insignificant defects can be eliminated by processing with a fine-grained emery paper, or a frictional surface of an old brake boot. In case of identification of deep damages give drums to a pro-point (within admissible range), or make their replacement.



  1. According to instructions grease working elements of the wheel cylinder and make assembly of the last.
  1. Assembly is made as it should be, the return to an order of dismantle of components, - track that the lever of automatic adjustment correctly nestled on a regulator cogwheel. Do not forget to grease points of fastening of springs, track observance of requirements of Specifications of the Head the Brake system to efforts of tightening of carving fixture.
  1. Before installation to the place of a drum measure the outer diameter of assembly of the boots put on a brake board, then measure the internal diameter of a drum. Determine by way of subtraction of result of the first measurement from result of the second the size of a side play of landing of boots, - the result of calculation should not exceed the limit of admissible range.