Audi 80/Avant (B4)

Audi 80/Avant
The description
System of release of the fulfilled gases
Cooling system
Fuel tank and the fuel pump
The air filter and intake channels
Injection system
- Coupling
   Drive of management of coupling
   Coupling service life
   Coupling check
   Check of a hydraulic drive of coupling
   Coupling removal
   The list of malfunctions
Transmission and transmission
Suspension bracket and steering
Brake system
Antiblocking system of brakes
Wheels and tyres
body electrosystem
Ignition system
Signalling devices
Devices and auxiliary devices
Heating and ventilation
Body elements
Search of malfunctions

Check of a hydraulic drive of coupling


  1. If coupling is divided correctly the hydraulic drive of coupling in any case too is perfectly in order.
  2. If coupling is divided badly or the pedal fails without resistance it is clear that air has got to a hydraulic drive. Simple removal of air in this case will not help – it is necessary to find and repair not tight place. After that it is possible to be engaged in air removal. Other reasons on which coupling is not divided correctly, are specified in the list of malfunctions in the end of the head.
  3. Who wishes to inspect just in case a hydraulic drive of coupling, should search for smudges of a brake liquid on the main cylinder (above at a coupling pedal) and in the working cylinder (near a transmission).
  4. Damp from oil coupling cylinders are not tight and should be replaced. But without thorough clearing of area round the working cylinder the origin of an oil stain on it can be defined with great difficulty.

 The help: in hydraulic system of coupling the liquid though arrives also from a tank with a brake liquid, however at a leaking in a hydraulic drive of coupling danger does not threaten brake system. The intaking branch pipe of a hydraulic drive of coupling is located in a tank rather highly so always there is enough of a liquid for work of brakes.

Removal of the main cylinder of coupling


  1. To select probably большее quantity of a liquid from a tank with a brake liquid (for example, an old syringe).
  2. To turn off a shelf at the left under the instrument panel (the Salon see)
  3. To enclose under the main cylinder an old rag, to remove bringing hose and to allow to the liquid rests to flow down in a rag.
  4. In a motor compartment to the left of the amplifier of brakes to turn off a pressure head hydroline to the working cylinder.
  5. To turn off two bolts (with internal шестигранником) fastenings of the main cylinder.
  6. To hook a lock washer swivel a finger (connection a pedal / the main cylinder) to squeeze out a finger.
  7. Now it is possible to remove the cylinder.
  8. At installation of the new cylinder it is necessary to adjust a rod which presses on the piston of the main cylinder so that the coupling pedal settled down approximately on 10 mm over a brake pedal.
  9. It is obligatory to pay attention: the returnable spring should return a pedal correctly. Thus the pedal in (rest) starting position should not rest against an arm of the pedal block.
  10. For adjustment to weaken a counternut on a pushing bar and to turn a bar to the left or to the right round its own axis. Then again to tighten a counternut.
  11. To clean air from a hydraulic drive of coupling to (pump over).

 The help: the coupling pedal in Audi 80 is supplied by a spring located above a dead point. It helps by pressing a pedal, however after release pedals squeezes out it again in a starting position. If the pedal does not come back, it means that air or bearings of a pedal or a spring has got to a hydrodrive заедают.

Removal of the working cylinder of coupling


  1. To raise and fix the left forward party of the car.
  2. To turn off a pressure head hose of a hydraulic drive of the working cylinder – it is cautious, the brake liquid which is necessary for collecting follows.
  3. To weaken a fixing bolt on the cylinder, to extend the working cylinder from картера transmissions in a direction back.
  4. If necessary to use an aerosol for removal of a rust and mount.
  5. Slightly to grease the new cylinder on unpainted walls of the case, on driving a pusher to put paste MoS2.
  6. To insert the working cylinder in картер transmissions and to press so that it was possible to screw in a fixing bolt in a carving on the transmission case (25 Nm).
  7. To pump over a hydraulic drive of coupling.

Prorolling of a hydraulic drive of coupling

If for you on hand is not available applied usually for this purpose in a device workshop, can pump over coupling by the same method, as brake system (the head Brake system) or, almost lost-free, next way:


  1. To open the valve of prorolling of one of forward wheels and the valve of the working cylinder of a hydrodrive of coupling everyone approximately on one and a half turn.
  2. To connect both valves a hose.
  3. Now some times slowly and cautiously to press a brake pedal that the brake liquid from a forward brake has been pressed through in a hydraulic drive of coupling.
  4. Not to press with force, differently the hose can come off!
  5. To watch level of a brake liquid in a tank.
  6. If air vials from a coupling hydrodrive do not rise any more from a tank with a brake liquid, means, it is possible to close both valves and to remove a hose.
  7. To check up level of a brake liquid!