Audi A4

since 1994 release

Repair and operation of the car

A4 Audi
+ Running gear
+ Regular servicing
+ Engines
+ Turbo-supercharging
+ System of an exhaust
+ Cooling system
+ Fuel tank and fuel pump
+ Air filter and channels of absorption
+ System of injection
+ Coupling
+ Transmission and main transfer
+ Suspension bracket of wheels and steering
- Brakes
   Independent work on brake system
   So the brake system works
   Check of brakes
   Brake fluid
   Check of level of brake fluid
   Check of brake system on tightness and existence of damages
   Replacement of brake fluid
   Disk brakes
   Measurement of thickness of overlays of forward disk brakes
   Check of a condition of brake disks
   Replacement of overlays of disk brakes
   Back disk brakes
   Measurement of overlays of back disk brakes
   Emergency brake
   Check of idling of the lever of the emergency brake
   Main brake cylinder
   Brake amplifier
   Check of the brake amplifier
   Works on hydraulics of brake system
   Pumping of brake system
   The help at malfunctions
   ABS and EDS
   What does ABS?
   Function of separate knots
   Electronic system of distribution of brake effort (EBV)
   Violations in work of ABS system
   Electronic blocking of differential (EDS)
+ Wheels and tires
+ Electrotechnical equipment
+ System of ignition
+ Lighting
+ Alarm equipment
+ Tools and devices
+ Heating and ventilation
+ body Details
+ Salon
Search of malfunctions
Technical characteristics

Pumping of brake system

The brake system has to be pumped over after repair of the hydraulic drive if air gets to brake cylinders and to brake tubes.


  1. Fill a broad tank with fresh brake fluid and during pumping constantly watch (!) timely addition of liquid before its level falls. Otherwise air will again be soaked up.
  2. Sequence of actions: behind on the right; behind at the left; ahead on the right; ahead at the left.
  3. Remove a dustproof cap from the pumping valve.
  4. Put on a transparent hose (as from system of washing of glasses) the wiped union and lower the free end of a hose in the capacity which is partially filled with brake fluid.
  5. Let your assistant, swinging a brake pedal, will create brake pressure.
  6. Unscrew the pumping valve on the corresponding wheel approximately on 11/2 turns and lower pressure. Thus the assistant holds a foot on a pedal and wrings out it.
  7. Close the valve and again pump up pressure.
  8. Also open the valve.
  9. Repeat this process until in a hose vials of air are not visible any more. (If the hydraulic system strongly became empty, pump over it twice.) In such a way via the valve brake fluid and, certainly, together with it air is pumped over.
  10. If vials of air are not present more, let your assistant hold a pedal in the lowest situation, and you close the pumping valve at this time. Tighten it carefully, differently will strip a thread.
  11. Pump over systems on other brakes of wheels in just the same way.

 Council: If the brake system on the above method is not pumped over, despite numerous repetitions of this process (vials of air are still visible), you have to close all valves of pumping, start the engine and several times press a brake pedal. Then once again pump over system.

At the left: pumping of brakes on a forward support. The valve of pumping (1) opens SW 7 key. The transparent synthetic hose is put on the valve (2) and the extorted brake fluid merges in the prepared capacity (3).

On the right: if brake tubes (2) and brake hoses (4) are connected by metal arms (3) to a running gear or to a body, there has to be a springing arm for a hose (1). Such key is suitable for a detachment of brake tubes (5)