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


Brake liquid

This yellowish – and, by the way, poisonous and aggressive in relation to an autovarnish – a liquid does not corrode rubber and metal parts. It remains even at a minus 40С more enough fluid, and its boiling point is located, despite the mentioned fluidity, on 260С.

But the brake liquid possesses also one very unpleasant property: it easily absorbs water, it гигроскопична. Water can really get to a brake liquid, for example through humidity of air: through a compensatory tank, and also microscopic not tight places on hoses of brake system and rubber cuffs. Full впитывание waters, however, does not lead to corrosion of metal parts of system, but to strong decrease in a boiling point. At only 2,5 % of the maintenance of water the boiling point is already only on 150С.

It is dangerous at high loading on brakes because in this case they strongly heat up. Close разогретых brakes in a working liquid air vials can be formed. As air is compressed – the brake pedal will fail in a floor! In this case can help only fast подкачивание a brake pedal. Especially dangerously this effect is shown at braking of the car after strong loading on brakes. Because of absence blowing a counter stream elements of brakes heat up even more strongly; the greatest temperature is reached approximately after 15 mines of parking. Only after half an hour the temperature of a brake liquid again falls to the normal. Therefore the servicing plan профилактически orders replacement of a brake liquid each two years.

The brake liquid should correspond to standard FMVSS116DOT4. All liquids marked thus without fears can be mixed one with another.