Mercedes C-Class

W203 since 2000 of release

Repair and car operation



Mercedes-Benz
+ Mercedes-Benz Cars of a class C (W-203)
+ Operation manual
+ Routine maintenance
+ Engine
+ cooling and heating Systems
+ Power supply system and release
+ engine Electric equipment
+ Manual transmission
+ Automatic transmission
+ Coupling and power shafts
- Brake system
   Specifications
   Replacement of blocks of a forward disk brake
   Removal and installation of a forward support
   Replacement of back brake shoes
   Removal and installation of a back support
   Removal and installation of a brake disk
   Check of a brake disk
   Dual main brake cylinder
   Replacement of brake shoes of the parking brake
   Removal and installation of a cable of a drive of the parking brake
   Removal and installation of the switch of a stoplight
   Air removal from brake system
   Removal and installation of a brake hose
   Check of the amplifier of a brake
+ Suspension bracket and steering
+ Body
+ Onboard electric equipment






Air removal from brake system

Corrected the treatment of brake liquid

The remark on security measures

Brake liquid is poisonous. At all do not soak up her mouth or through a hose. Store brake liquid only in bottles casual access to which is excluded.

At the treatment of brake liquid it is necessary to observe the following rules:

Brake liquid is aggressive and for this reason should not come into contact to a paint and varnish covering of the car. If it occurred, immediately wipe a place of contact and wash out water.

Brake liquid is hygroscopic, i.e. it absorbs moisture from air. Store brake liquid only in the closed vessels.

Take measures to that children casually could not drink brake liquid.


Brake liquid which was already used once in brake system of the car, should not be applied. At removal of air of their brake system also apply only new liquid.

Specification of brake liquid: DOT4.

Level of brake liquid should be in the tank between MAX and MIN marks.


Brake liquid should not come into contact to mineral oil. Even insignificant traces of mineral oil do brake liquid not suitable for the use or lead to failures of brake system. Cuffs and laying of brake system are damaged at contact to mineral oils. Do not apply to rag cleaning, with traces of mineral oils.

To washing and cleaning of brake cylinders, hoses and pipelines apply only new brake liquid.

Replace brake liquid each 2 years, whenever possible after a cold season.

Brake liquid represents dangerous liquid which cannot be poured out or out somewhere by no means with a household waste. The local administration should provide information on the closest places of delivery of brake liquid.


Air removal from brake system

After carrying out repair of brake system during which its opening was made, air can get to system. In this case it is necessary to remove air from system. An existence sign in pipelines of system of air is the pliability of a pedal of a brake by pressing it. In this case it is necessary to eliminate a leakage and to remove air from system.

On HUNDRED brake system it is, as a rule, filled with liquid, and air from it is removed by means of the special device. Remark: When using the specified adaptation pressure of filling of system should not exceed 1 atm. This operation can be carried out as well without the specified device. In this case air from brake system is removed by kachatelny movements of a pedal of a brake what needs the help of the assistant.

If air got into any separate brake cylinder, it is necessary to delete air from all brake system and by that from each wheel cylinder. If only one support, as a rule, is replaced or under repair it appears sufficient to remove air from the corresponding brake cylinder.

The remark on security measures

If one of chambers of the tank of brake liquid is completely emptied (for example, in the presence of a leakage in brake system or if at removal of air forgot to add in the tank liquid), in system air which gets to the pump ABS is sucked in. Air from brake system in this case should be removed on HUNDRED with use of the special device.

Sequence of removal of air: back right brake, back left brake, forward right and forward left brake and working cylinder of coupling.

Carefully open gates for removal of air so that not to break them. It is recommended to spray a gate carving approximately in 2 hours prior to air removal by rust solvent. If the valve does not turn away, recommended to perform this operation on HUNDRED.

During air removal periodically watch the liquid tank. Level of liquid should not fall too low, otherwise via the tank air can get to system. Surely fill system with only new brake liquid.


Unscrew a cover of the tank of brake liquid and put it aside. Fill system with liquid to MAX mark.

Mark with paint the provision of wheels concerning naves. It will allow to establish at assembly otbalansirovanny wheels in their former situation. Weaken bolts of fastening of a wheel before a car poddomkrachivaniye. Lift the car, put it on supports and remove wheels.

Security measures

Operation of lifting and car installation on supports is connected with danger! Therefore before carrying out operation familiarize with Poddomkrachivaniye's Section and Introduction towage to the management.

 PERFORMANCE ORDER

1. Remove a dustproof cap (1) from the gate for air (2) removal on the wheel cylinder.

2. Clear the gate, put on it a pure hose. Other end of a hose lower in a bottle filled on a half with brake liquid. To an otvorachivaniye of the gate apply a special key (HAZET 1968-N).

3. Establish or hold a bottle for liquid at height not less than 30 cm over the union for air removal. Thus possibility of hit of air in brake system through an union carving is excluded.

4. Ask the assistant to "shake" a brake pedal until in system pressure will not rise. It will be felt on resistance of a pedal of a brake.
5. After achievement of necessary pressure completely press through a pedal and hold her foot.
6. Unscrew a cap key the gate on the wheel cylinder approximately on a half of turn.
7. When liquid will start to arrive in a bottle, watch that the hose end always was in a bottle below liquid level.
8. As soon as pressure of liquid упадёт, close the gate.
9. Repeat process of a kachaniye of a pedal until pressure will be created. Squeeze out a pedal, leave on a pedal a foot foot, open the gate of removal of air so that pressure fell down, and then close the gate.
10. Repeat process of removal of air of the wheel cylinder until in the liquid arriving in a bottle, there will be no air vials.
11. Carefully tighten the gate for air removal by the moment 7Нм.
12. After completion of operation remove a hose from the union for removal of air and put on the gate a protective cap.
13. Similarly, observing the sequence specified above, remove air from other brakes.
14. Establish to the place of a wheel so that the marks put at removal coincided. Previously grease with a thin layer of bearing greasing aligning belt of a disk of a wheel on a nave. Bolts of fastening of wheels do not grease. Rusty bolts replace. Wrap bolts. Lower the car on wheels and tighten bolts cross-wise the moment 110Нм.
15. After completion of process of removal of air fill the tank with brake liquid to a mark of MAX and screw a cover.

Carry out reliability control:

· Whether brake hoses are fixed?
· Whether the brake hose in the holder is fixed?
· Whether unions for air removal are tightened?
· Whether enough of brake liquid is filled in?
· On the working engine check tightness. For this purpose press a brake pedal effort of 200-300 N (20-30 kg) during 10 pages. The pedal should not weaken. Check all accessions on tightness.
16. Check work of brake system on the road with not heavy traffic. For this purpose it is necessary to carry out, at least, one strong braking with use of action of ABS (it is felt on a pulsation of a pedal of a brake).

Watch closely transport following you.

Brake liquid represents dangerous liquid which cannot be poured out or out somewhere by no means with a household waste. The local administration should provide information on the closest places of delivery of brake liquid.