Audi 80/Avant (B4)

since 1991-1995 of release

Repair and car operation

Audi 80/Avant
+ Technical specification
+ Engines
+ System of production of the fulfilled gases
+ cooling System
+ Fuel tank and fuel pump
+ Air filter and airintaking channels
+ injection System
+ Coupling
+ Transmission and transmission
+ Suspension bracket and steering
- Brake system
   Check of brake mechanisms
   Brake liquid
   Check of level of brake liquid
   Check of tightness of brake system
   Replacement of brake liquid
   Disk brake mechanisms
   Measurement of thickness of blocks of the disk mechanism
   Control of a condition of brake disks
   Replacement of blocks of disk brake mechanisms
   Drum-type brake mechanism
   Measurement of brake shoes of the drum-type mechanism
   Check of a course of a pedal of a brake
   Disk brake mechanism of back wheels
   Measurement of thickness of blocks of back disk brakes
   Check of a free wheeling of the lever of the parking brake
   Main brake cylinder
   Amplifier of brakes
   Check of the amplifier of brakes
   Regulator of brake forces
   Repair of a hydraulic drive of brakes
   Pumping of brake system
   List of malfunctions
+ Anti-blocking system of brakes
+ Wheels and tires
+ Body electrosystem
+ ignition System
+ Lighting
+ Signalling devices
+ Devices and auxiliary devices
+ Heating and ventilation
+ body Elements
+ Search of malfunctions
+ Specifications

Check of a course of a pedal of a brake


  1. Press a brake pedal a hand.
  2. The free wheeling should make at most 1/3 from the general course of a pedal.
  3. Longer free wheeling of a pedal says that brake shoes wore out till the minimum thickness and should be replaced.
  4. Too long course of a pedal can be caused and the jammed brake shoes or a prirzhavevshy support of the brake mechanism.
  5. Probably, air got to brake system.

Removal of a brake drum

At the removed brake drum in the brake mechanism of a back wheel we see the following elements

1–forward brake shoe;
2–adjusting wedge;
3–wheel brake cylinder;

4–hummock drive of the parking brake;
5–lever of turning on of the parking brake;
6–back brake shoe.

The brake drum can be removed and without removing a wheel. In this case:


  1. To turn out one wheel bolt.
  2. To raise the car behind.
  3. To turn a rim or a brake drum so that the opening for a bolt appeared in front above on a car course.
  4. Through an opening for a bolt to wring out an adjusting wedge up – brake shoes thereby are wrung out.
  5. To remove a koronchaty cap of a wheel (head the Suspension bracket and a steering).
  6. To unbend and take out safety шплинт in the bearing of a nave of a wheel.
  7. To remove a koronchaty clamp, to unscrew a six-sided nut, to remove a persistent washer and the external bearing of a wheel.
  8. To remove a brake drum.
  9. At installation to adjust люфт the bearing of a nave of a wheel (see head the Suspension bracket and a steering).
  10. To bring blocks to a brake drum by disposable strong pressing a brake pedal.

 Help: if at the old car it is impossible to wring out upward rusted adjusting wedge, ask the assistant to press a brake pedal – while you will wring out a wedge. Then it is necessary to release a pedal of a brake and only now to take out a screw-driver from an opening, differently the wedge again will fall down. Watch that the pressing a pedal was made only if both brake drums are established.

Check of a condition of brake drums


  1. The rubbing surface in a drum should be whenever possible smooth.
  2. If deep furrows or scratches are visible (because of the brake shoes worn out to rivets), the drum can be chiseled.
  3. Internal diameter of new brake drums makes 230 mm.
  4. After boring internal diameter should not be more than 231 mm, otherwise it is necessary to replace both brake drums.
  5. It is necessary to apply thicker blocks to the chiseled brake drums.

Removal of the cylinder of the drum-type brake mechanism

Parts of the removed drum-type brake mechanism. Shooters show, where it is necessary to hang springs.

1–forward brake shoe;
2–a clip with a spring, a spring plate and a fixing pin;
3–press bar;
4–returnable spring;
5–adjusting wedge;
6–tension spring of an adjusting wedge;

7–bottom returnable spring;
8–main spring;
9–lever of turning on of the parking brake;
10-a frictional slip on a back brake shoe;


  1. To remove a brake drum.
  2. To remove brake shoes.
  3. To turn out the pumping valve.
  4. To disconnect a brake hose. If you are not going to establish at once the new brake cylinder, it is necessary to squeeze out a pedal of a brake and to leave it in this situation, to prevent unnecessary loss of brake liquid.
  5. To take out two fixing bolts behind on a guard of the drum-type brake mechanism and to remove the brake cylinder.

Removal of brake shoes


  1. To remove a brake drum.
  2. To wring out пассатижами a spring plate of the holder of brake shoes, to turn on 90 ° (holding a fixing pin behind at a guard that it did not rotate together with a guard) and to remove them, then to remove springs.
  3. To unhook a returnable spring of an adjusting wedge.
  4. To separate a brake shoe from the bottom support and the piston of the brake cylinder.
  5. To extend an adjusting wedge from a press bar.
  6. To fasten the main spring to a press bar and a brake shoe. As it is necessary to establish a spring, it is shown in drawings.
  7. To establish a brake shoe on a press bar, to insert from above an adjusting wedge. Its ledge is directed towards a brake shoe.
  8. To establish the brake lever of a passive block in a ledge of a press bar, to fasten the top returnable spring.
  9. To hang a cable of a drive of the parking brake at yet not fixed brake shoes on the lever of turning on of the parking brake.