Audi A4, S4

since 2000 release

Repair and operation of the car

Checks of brake system. Adjustment of the parking brake

The dust which is formed as a result of wear of slips and accumulating on components of the brake mechanism may contain asbestos hazardous to health. Do not blow this dust by means of compressed air and do not inhale it! Do not use solvents on the basis of gasoline for removal of dust. Dust should be washed away a special cleaner of brake system or methyl alcohol in drain capacity. After rubbing the component of brake system a damp rag should be held this rag and contents of drain capacity in the closed and signed container. Further, whenever possible, try to use the components which are not containing asbestos.

Except checks through the established time intervals a condition of brake mechanisms it is necessary to carry out every time at removal of wheels or at emergence of signs of malfunction in system. For driving safety the procedures of check of brake system described below are the most important of all procedures for service of the car made by you.

Signs of malfunctions in brake system

Disk brake mechanisms can have the built-in indicators of wear of frictional slips which signal that wear of slips reached critical size. Thus slips should be changed immediately, differently brake disks will be damaged and they will need expensive repair.

Any of the listed below signs can indicate potential defect of brake system:

1. When squeezing a pedal of a brake the car "takes away" in one party.
2. Brake mechanisms when braking make the scraping or squealing sounds.
3. The pedal of a brake has the excessive course.
4. The pedal of a brake pulses (it normally only during the work of ABS system).
5. Leak of brake fluid is observed (usually on inside of the tire or a wheel).

In case of detection at least of one of these signs immediately examine elements of brake system.

Brake lines and hoses

In brake system steel brake tubes, except for the flexible reinforced hoses at forward wheels and as connections at the back bridge are generally used. Regular survey of all these lines is very important.

PERFORMANCE ORDER

The car and reliably establish to Poddomkratta it on support. Remove wheels (address to the Section Check of a Condition of Tires and Pressure in them. Designation of tires and disks of wheels. Rotation and replacement of wheels and to the head's materials Governing bodies and methods of safe operation). Check all brake lines and hoses for existence of cracks and attritions in their external covering, leaks, swellings and deformations. Check brake hoses in forward and back parts of the car for existence of signs of a softening, cracks, deformations or wear as a result of friction about other components. Check all nipple connections for existence of signs of leaks and make sure of reliability of fastening of all bolts and clips of brake hoses. Bend hands in one and other parties a brake hose to reveal damages. It is not necessary to twist hoses. Watch the direction of the color line put on a hose! Turn a steering wheel to the right and to the left against the stop. Hoses should not touch car design elements thus. At detection of leak of liquid or their damages it is necessary to eliminate immediately. For more detailed description of procedure of repair of brake system address to the Head Brake system.

Check of thickness of brake shoes

Thickness of external brake shoes can be checked through an aperture in a wheel disk by means of a pocket small lamp. The internal block can be checked by means of a pocket small lamp and a mirror. If it is necessary to estimate more precisely block thickness, it is necessary to remove a wheel and to measure a block by a caliper.

Experience shows that wear of a brake shoe of a wheel from the forward passenger is more, than from the driver. Therefore for check of thickness of a brake shoe it is recommended to remove a wheel from the forward passenger.

PERFORMANCE ORDER

Note paint the provision of a forward wheel in relation to a nave. It will allow to establish the balanced wheel in the working situation. Weaken bolts of fastening of a wheel. Thus the car has to stand on the earth. Lift forward part of the car and establish on supports. Remove a forward wheel. (Shooters) internal and external blocks check thickness for illustrations through an aperture in a support. The limit of wear of thickness of brake shoes will be reached if the overlay of a block has thickness of 2.0 mm (7 mm together with a basis plate). In this case the brake shoe needs to be replaced, address to the Sections Removal and installation of front brake shoes and Removal and installation of blocks of brake mechanisms of back wheels. In practice, 1 mm of wear of a brake shoe corresponds at least 1000 km of run of the car. This rule corresponds to adverse service conditions of the car. In normal conditions wear of blocks is much less. At a thickness of block of 10.0 mm (with a basis plate) the block can be operated still not less than 3000 km. Check possibility of leak of brake fluid in supports. With leakage urgently repair a support (work HUNDRED). Visually check brake disks for existence of flutes, traces of impact of corrosion and cracks. The ventilated disks with cracks thickness in a hair and up to 25 mm long which cause of emergence the raised loading can be, do not need to be replaced. At cracks and grooves more than 0.5 mm in depth brake disks need to be replaced. Check thickness of brake disks, address to the Section of the Head Brake system. Establish into place forward wheels so that the tags put at removal coincided. Previously grease with a thin layer of a podshipnikovoysmazka the aligning wheel disk belt on a nave. Do not grease bolts of fastening of a wheel. Replace rusty bolts. Wrap bolts. Lower the car on wheels and tighten bolts cross-wise.

Check and extra earnings of the parking brake

Check

If the parking brake is pressed through one distance further to 5 teeth, it is necessary to regulate a brake.

Extra earnings of a brake

The parking brake is served as by 2 drum brakes located in back disk brakes. Thanks to it the parking brake wears out slightly. Owing to corrosion of the brake drum or pollution of brake shoes the brake moment can decrease. For achievement of optimum action of its brake it is necessary to earn extra.

PERFORMANCE ORDER

Pass on the dry, not having heavy traffic road. At a speed about 50 km/h establish a transmission in neutral situation. Extend the handle of the parking brake. Thus stop the car. When braking by the parking brake the signal of braking does not light up. For this reason be especially attentive in relation to the transport moving behind. Continue the movement on the car with a constant speed about 50 km/h. Extend the handle of the parking brake, approximately on 10 sec. and release. If the parking brake is badly tightened, after its cooling repeat braking process. If the parking brake after check is released badly or after extra earnings and adjustments is tightened on the one hand, check brake shoes and cables, if necessary replace.