Audi 80/Avant (B4)

since 1991-1995 release

Repair and operation of the car

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
+ System of injection
+ Coupling
+ Transmission and transmission
+ Suspension bracket and steering
- Brake system
   Check of brake mechanisms
   Brake fluid
   Check of level of brake fluid
   Check of tightness of the brake system
   Replacement of brake fluid
   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 brake mechanism
   Measurement of brake shoes of the drum mechanism
   Check of the 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 the hydraulic drive of brakes
   Pumping of the brake system
   List of malfunctions
+ Anti-blocking system of brakes
+ Wheels and tires
+ Body electrical system
+ System of ignition
+ Lighting
+ Signaling devices
+ Devices and auxiliary devices
+ Heating and ventilation
+ Body elements
+ Search of malfunctions
+ Specifications

Check of tightness of the brake system

For monitoring procedure the lower part of a body has to be dry that you could make out untight places. Brake fluid gets also under dirt. Places, dark from moisture, force to assume leak.


  1. Check all places of connections, and also supports of the disk brake mechanism and guards of the drum brake mechanism behind which wheel brake cylinders are located.
  2. Hoses of the brake system should not be damp, swelled or rubbed. Otherwise they need to be replaced.
  3. Pipelines of the brake system have a corrosion-resistant coating. If to damage this protective layer, then formation of a rust can begin. Therefore it is never impossible to clean serviceable pipelines of the brake system by means of the screw-driver, an emery cloth or a wire brush.
  4. If the protective layer is damaged, it is necessary to apply with a thin layer anticorrosion primer.
  5. Tubes with traces of a rust or squeezed need to be replaced.
  6. Whether all valves of pumping are protected by protective caps? They are on supports of disk brake mechanisms or in guards of drum brake mechanisms.
  7. You can carry out the improvised inspection of pressure in the brake system:
  8. Squeeze out a brake pedal with a full force.
  9. It should not give in and after several minutes of full loading, otherwise one of cuffs of the main brake cylinder is defective.
  10. Because of an untight cuff liquid level in a tank does not go down, however the squeezed liquid flows via the piston in the main brake cylinder on other party where pressure is absent.
  11. Untight places on cuffs of pistons of supports of disk brake mechanisms and brake cylinders of drum mechanisms can be distinguished in dark places on supports disk or guards of drum brake mechanisms.
  12. If you are not sure – address in a workshop.