Audi 80/Avant (B4)

Since 1991-1995 of release

Repair and car operation

Audi 80/Avant
+ The description
+ Engines
+ System of release of the fulfilled gases
+ Cooling system
+ Fuel tank and the fuel pump
+ The air filter and воздухозаборные channels
+ Injection system
+ Coupling
+ Transmission and transmission
+ Suspension bracket and steering
- Brake system
   Check of brake mechanisms
   Brake liquid
   Check of level of a brake liquid
   Check of tightness of brake system
   Replacement of a brake liquid
   Disk brake mechanisms
   Measurement of a thickness колодок the disk mechanism
   The control of a condition of brake disks
   Replacement колодок disk brake mechanisms
   The drum-type brake mechanism
   Measurement brake колодок the drum-type mechanism
   Check of a course of a pedal of a brake
   The disk brake mechanism of back wheels
   Measurement of a thickness колодок back disk brakes
   Check of a free wheeling of the lever of a lay brake
   The main brake cylinder
   The amplifier of brakes
   Check of the amplifier of brakes
   Regulator of brake forces
   Repair of a hydraulic drive of brakes
   Prorolling of brake system
   The list of malfunctions
+ Antiblocking system of brakes
+ Wheels and tyres
+ Kuzovnaja electrosystem
+ Ignition system
+ Illumination
+ Signalling devices
+ Devices and auxiliary devices
+ Heating and ventilation
+ Body elements
+ Search of malfunctions
+ Specifications


Prorolling of brake system

Prorolling of brake system in a forward support of the disk brake mechanism:
The valve of prorolling (1) opens a key of 7 mm. The transparent hose (2) lowered in the prepared capacity (3) is put on the valve.

Prorolling of brake system is necessary after repair of a hydraulic drive of brake system when air has got to the brake cylinder or the pipeline:


    To fill a receiver with a new brake liquid, and also during prorolling to watch that the liquid was in due time added to certain level. Otherwise air again will get to a tank. To remove a dustproof cap from the prorolling valve (sequence of works: behind on the right; behind at the left; in front on the right; in front at the left). To put on a transparent hose (for example, type of a hose of system of washing of glasses) on the valve wiped clean and to lower its free end in the capacity partially filled with a brake liquid. Ask the assistant to create pressure in system by pressing a brake pedal. To open the ventilating valve on a corresponding wheel approximately on 1—1,5 turns and to lower pressure. The assistant thus a foot squeezes out and releases a pedal. Again to close the valve and to create pressure. To open the valve as it has already been made. To repeat this process until in a hose it will not be visible any more any air vials. (At much devastated hydraulic system to spend prorolling twice.) Thus, through the valve the brake liquid and, of course, air is pumped over. If it is not visible air vials any more the assistant should hold a pedal of a brake pressed to the full while you close the valve. To tighten cautiously, differently it is possible to strip a thread! To remove air from brakes of other wheels in the same way.