Audi A4

Since 1994 of release

Repair and car operation

Audi А4
+ Running gear
+ Regular servicing
+ Engines
+ Turbo-supercharging
+ Exhaust system
+ Cooling system
+ Fuel tank and the fuel pump
+ The air filter and channels всасывания
+ Injection system
- Coupling
   Coupling functioning
   Coupling actuating
   Coupling check
   Check of hydraulics of coupling
   The help at malfunctions
+ Transmission and the main transfer
+ Suspension bracket of wheels and steering
+ Brakes
+ Wheels and tyres
+ The electrotechnical equipment
+ Ignition system
+ Illumination
+ The alarm equipment
+ Tools and devices
+ Heating and ventilation
+ Body details
+ Salon
Search of malfunctions
Technical characteristics

Check of hydraulics of coupling

In a bell of coupling of the dismantled engine knots of management of coupling are visible

1 – the deenergizing lever (on it force of the main cylinder of coupling operates);
2 – выжимной the bearing;

3 – an entrance shaft of a transmission.

Over a coupling pedal (figure "1" designates the lever) (5) working cylinders of coupling and both fixing bolts (3 and 4) are visible a rubber cuff. Figure "2" designates a lock collar шарнирного a finger which should be taken out at dismantle.


  1. If coupling is switched off correctly, its hydraulic system in any case is perfectly in order.
  2. But if it is switched off badly or the pedal fails without resistance for certain air has got to hydraulic system.
  3. Simple removal of air here will not help – it is necessary to find a place of leak and to repair it. Now you can remove air from system. The information on other causes of defect of coupling you will find in the end of this chapter in section the Help at malfunctions.
  4. For the purpose of preventive check of hydraulic system of coupling look for traces of a brake liquid on the working cylinder (above on a coupling pedal) and on the main cylinder (on a transmission).
  5. The cylinders of coupling moistened with oil негерметичны also are subject to replacement. Though the origin of an oily dirt on the main cylinder is defined hardly without thorough cleaning of this site.

 Council: the coupling Hydraulics receives the liquid from a tank with a brake liquid, but at a leaking in this area danger does not threaten brake system. The branch pipe of a fence of a liquid in hydraulic system of coupling is on a tank highly enough, therefore for brakes always there is liquid enough.

Dismantle of the working cylinder of coupling


  1. Suck away as much as possible liquid from a broad tank (by means of the big medical syringe).
  2. Dismantle control panel facing at the left below (the head Salon).
  3. Enclose under the working cylinder an old rag, disconnect submitting hose and allow to flow down to the liquid rest in a rag.
  4. From outside an impellent compartment unscrew a delivery hose to the main cylinder.
  5. Unscrew two fixing bolts with internal шестигранниками at the working cylinder.
  6. Cast away back a lock collar шарнирного a finger (connection of a pedal and the working cylinder), squeeze out a finger.
  7. Now it is possible to remove the cylinder.
  8. At installation of the new cylinder the rod pressing the piston of the working cylinder, should be adjusted so that the coupling pedal was approximately on 10 mm above a brake pedal.
  9. Necessarily track: the returnable spring should wring out a pedal properly. Thus the pedal in rest position should not adjoin above to the arm. Otherwise the piston of the working cylinder in rest position cannot move to a back emphasis.
  10. For adjustment ослабьте a counternut on a press rod also turn press a rod to the left or to the right about the axis. Then again tighten a counternut.
  11. Pump over hydraulic system of coupling.

 Council: the coupling Pedal in Audi A4 is supplied by a so-called spring with the top dead point. It helps by pressing a pedal, but after foot removal returns it in a starting position. If the pedal does not come back back air or a heavy course of a pedal or a spring has got to hydraulic system.

Dismantle of the main cylinder of coupling


  1. Lift and fix a forward left-hand side of the car.
  2. Unscrew from the main cylinder a delivery hydraulic hose – be cautious, the brake liquid thus follows.
  3. Substitute capacity.
  4. Loosen the a fixing bolt on the cylinder, take out the main cylinder back from the transmission case.
  5. If it is necessary, help itself an anticorrosive spray and монтировочным the lever.
  6. Slightly oil surfaces of the case of the new cylinder, grease with paste MoS2 a pusher.
  7. Insert the main cylinder into the case of a transmission and press it until it will be possible to screw up fixing bolts in a carving on a transmission (25 Nanometers).
  8. Pump over hydraulic system.

Removal of air from hydraulic system of coupling

At whom is not present the usual device for a workshop for откачки air, deletes air from hydraulic system of coupling the same as from brake – almost unmistakably – next way:


  1. Open a nipple for air release on a brake of a forward wheel and a nipple on the main cylinder of coupling approximately on 1,5 turns everyone.
  2. Connect both nipples a hose.
  3. Now some times slowly and cautiously press a brake pedal that the hydraulic liquid from a brake of a forward wheel has been wrung out through coupling hydraulics.
  4. Do not press on a pedal with force, differently the hose will break!
  5. Do not lose sight of liquid level in a broad tank.
  6. If in a broad tank vials of air from hydraulic system of coupling both nipples are screwed up also a hose do not arrive any more acts in film.
  7. Check up level of a brake liquid!