Audi 80/Avant (B4)

Since 1991-1995 of release

Repair and car operation

Disk brake mechanisms do not operate in the self-amplifying image, as, for example, the drum-type. Much higher brake force is necessary. Therefore Audi 80 it is supplied by the pneumatic amplifier of a brake drive adding about 60 % of brake force. Despite it, the brake pedal is directly connected with the brake piston in the main brake cylinder so it is possible to brake and at the failed amplifier. But necessary pressure upon a pedal in this case needs to be increased several times.

Additional force is provided with the lowered pressure from an inlet collector. The amplifier of brakes is connected by a hose with a final collector. At braking the difference in pressure between external pressure of air and the lowered pressure in a final collector shifts the big elastic diaphragm and in addition presses on the piston in the main brake cylinder. If the engine is not got, the amplifier cannot develop any (additional) brake force. If the engine suddenly глохнет still there is a small reserve for a quantity of braking; but then it is necessary to hope only for force of feet.

The vacuum pump

For improvement поддерживания brake force the 5-cylinder engine is equipped by the additional vacuum pump established at the left at a head of the block of cylinders and set in motion by a camshaft. Thanks to it the lowered pressure in hoses to the amplifier of brakes increases.