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
   Drive of management of coupling
   Coupling service life
   Coupling check
   Check of a hydraulic drive of coupling
   Coupling removal
   List of malfunctions
+ Transmission and transmission
+ Suspension bracket and steering
+ Brake system
+ 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

bitrix help desk, ооо.
bitrix help desk, ооо.

Check of a hydraulic drive of coupling


  1. If coupling is divided correctly, a hydraulic drive of coupling in any case too as it should be.
  2. If coupling is divided badly or the pedal fails without resistance, it is clear that air 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 at the end of head.
  3. Who wants to inspect just in case a hydraulic drive of coupling, should look for smudges of brake liquid on the main cylinder (above at a coupling pedal) and in the working cylinder (near a transmission).
  4. Damp from oil cylinders of coupling are not tight and should be replaced. But without thorough cleaning of area round the working cylinder on it it will be possible to define an origin of an oil spot with great difficulty.

 Help: in hydraulic system of coupling liquid though arrives also from a tank with brake liquid, however at a leakage 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 liquid enough for work of brakes.

Removal of the main cylinder of coupling


  1. To select probably bigger amount of liquid from a tank with brake liquid (for example, an old syringe).
  2. To turn off a shelf at the left under the dashboard (see. Salon)
  3. To enclose under the main cylinder an old rag, to remove bringing hose and let's to the remains of liquid flow down in a rag.
  4. In a motor compartment to the left of the amplifier of brakes to turn off the pressure head hydroline to the working cylinder.
  5. To turn off two bolts (with an internal shestigrannik) fastenings of the main cylinder.
  6. To hook a lock washer of a sharnirny 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 pedal of coupling 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 a starting position (rest) should not rest against an arm of the pedal block.
  10. For adjustment to weaken a lock-nut 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 lock-nut.
  11. To clean air from a hydraulic drive of coupling to (pump over).

 Help: the coupling pedal in Audi 80 is supplied with a spring located above a dead point. It helps by pressing a pedal, however after an otpuskaniye of a pedal 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 got to a hydraulic actuator jam.

Removal of the working cylinder of coupling


  1. To raise and fix the left forward side of the car.
  2. To turn off a pressure head hose of a hydraulic drive of the working cylinder – it is careful, brake liquid which is necessary for collecting follows.
  3. To weaken a fixing bolt on the cylinder, to extend the working cylinder from a transmission case in the 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 a driving pusher to put MoS2 paste.
  6. To insert the working cylinder into a case of a transmission and to press so that it was possible to screw in a fixing bolt in a carving on the transmission case (25 N • м).
  7. To pump over a hydraulic drive of coupling.

Pumping 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 (head «Brake system») or, almost without loss, the next way:


  1. To open the valve of pumping of one of forward wheels and the valve of the working cylinder of a hydraulic actuator of coupling everyone approximately on one and a half turn.
  2. To connect both valves a hose.
  3. Now several times slowly and carefully to press a brake pedal in order that brake liquid from a forward brake was 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 brake liquid in a tank.
  6. If air vials from a hydraulic actuator of coupling do not rise any more from a tank with brake liquid, means, it is possible to close both valves and to remove a hose.
  7. To check level of brake liquid!