Mercedes W124

since 1985-1995 of release

Repair and car operation



W124 Mercedes
+ Governing bodies and control devices
+ MAINTENANCE
+ 2. Maintenance (diesel engines)
+ ENGINE
+ 4. Repair of 6-cylinder petrol SOHC engines
+ 5. Repair of 6-cylinder petrol DOHC engines
+ 6. Repair of the diesel engine established in the car
+ 7. Major maintenance of engines
+ COOLING SYSTEM
+ FUEL SYSTEM
+ 10. System of injection of BOSCH CIS-E fuel (KE-JETRONIC)
+ 11. System of injection of BOSCH HFM fuel
+ 12. Fuel system of diesel engines
+ 13. Fuel system of diesel engines
+ SYSTEMS OF START, IGNITION
+ 15. System of ignition of 4-cylinder petrol engines
+ 16. System of ignition of four-cylinder petrol engines
+ PRESTARTING HEATING
+ TRANSMISSION
+ 19. Mechanical transmission
+ 20. Automatic transmission
+ POWER SHAFTS
- BRAKE SYSTEM
   22.2. General information
   22.3. Pumping of hydraulic brake system
   22.4. Brake pipelines and hoses
   + 22.5. Replacement of forward brake shoes
   22.6. Replacement of back brake shoes
   22.7. Forward brake disk
   22.8. Back brake disk
   22.9. Forward brake support
   + 22.10. Support repair
   22.11. Back brake support
   22.12. Main brake cylinder
   22.13. Vacuum amplifier of brakes
   22.14. Unilateral valve of the vacuum amplifier of brakes
   22.15. Adjustment of the parking brake
   22.16. Brake shoes of the parking brake
   22.17. Pedal of the parking brake
   22.18. Cables of the parking brake
   22.19. Stoplight switch
   22.20. Anti-blocking system (ABS)
   + 22.21. Elements of anti-blocking system
   22.22. The vacuum pump on models with diesel engines
+ SUSPENSION BRACKET
+ BODY
+ ELECTRIC EQUIPMENT
+ CHECK OF MALFUNCTIONS






22.12. Main brake cylinder

GENERAL INFORMATION

Prevention

The brake liquid used in hydraulic system of coupling is poisonous, therefore at its hit on skin it is necessary to wash out immediately this place a plentiful quantity of water. If liquid got to eyes or in an organism, it is necessary to address immediately to the doctor. Some liquids have property easily to ignite and can light up even from contact to hot knots of the car. Besides, the liquid used in hydraulic system of coupling, dissolves paint and plastic therefore at liquid hit on a paint and varnish covering of the car wash out it a plentiful quantity of water. Also this liquid is hygroscopic, i.e. absorbs moisture from air and therefore the liquid, being stored in open ware, it is not recommended to use a long time.


Removal

PERFORMANCE ORDER
1. Remove a weight wire from the accumulator.
2. Disconnect the electric socket from the sensor of level of brake liquid.
3. Press several times a pedal of a brake to fill with air the vacuum amplifier of brakes or to remove pressure in the hydraulic block of the servomotor.
4. Uncover a tank of brake system and, using a syringe, pump out brake liquid. Alternatively unscrew any union of pumping and, pressing a brake pedal, merge brake liquid through a plastic pipe in the corresponding vessel.
5. Disconnect from a popolnitelny tank of brake system a hose of supply of liquid in hydraulic system of coupling and close it a stopper.
6. Having pulled up, remove a popolnitelny tank from the main brake cylinder. Remove from the main brake cylinder rubber consolidation of a popolnitelny tank and close openings jams.
7. Clear places of connection of brake tubes to the main brake cylinder. Mark the brake tubes suitable to the main brake cylinder. Arrange pure rags under the main brake cylinder, unscrew nuts of fastening of brake tubes and take aside from the main brake cylinder brake tubes. Close the ends of tubes the corresponding jams.
8. Unscrew two nuts, fixing the main brake cylinder to the vacuum amplifier of brakes, and remove the main brake cylinder. Remove a sealing ring from a back part of the main brake cylinder.
Prevention

Removal of the main brake cylinder make only after a detachment it from a pusher of the vacuum amplifier of brakes, differently the vacuum amplifier of brakes will be damaged.


Repair


Prevention

On cars устанавлива ются two types of brake cylinders therefore at acquisition of details for the brake cylinder consider its type.


Main brake cylinder of the Teves model
1–sealing plugs of fastening of a popolnitelny tank;
2–sealing ring;
3–primary piston;
4–persistent washer;
5–lock ring;
6–sealing ring;
7–plug;
8–washer;
9–sealing ring;
10-sealing ring;
11-spring nest;
17-spring;
20-
secondary piston;
21-spring;
22-case of the main brake cylinder;
24-valve spring;
25-valve consolidation;
27-pin of fastening of the secondary piston;
28-valve pin;
B–an opening for supply of liquid;
C–compensatory openings;
D–openings for supply of liquid and compensation

PERFORMANCE ORDER
1. Clear all pollution from the case of the main brake cylinder.
2. Note an arrangement and remove from the main brake cylinder sealing plugs of a popolnitelny tank (see drawing).
3. Being careful, fix the case of the main brake cylinder in a vice with soft sponges. Using a steel core, press the piston into the main brake cylinder and take a pin of fastening of the secondary piston.
4. Repeatedly press the piston into the main brake cylinder and remove from a back part of the main brake cylinder a lock ring, a washer and a sealing ring.
5. Noting an arrangement of details, take from the main brake cylinder knot of the primary piston and a spring.
6. Knock with a back part of the case of the main brake cylinder about a board and take from it knot of the secondary piston and a spring.
7. Using methyl alcohol, clear all details of the main brake cylinder. Do not use gasoline which dissolves rubber details of brake system. Using the compressed air or pure rags, dry or wipe dry details of the main brake cylinder.
8. Check a condition of details of the main brake cylinder and, if necessary, replace. Special attention turn on a condition of channels of the main brake cylinder and pistons. In the presence of scratches, рисок, wear and traces of dot corrosion replace the main brake cylinder assembled.
9. Irrespective of a condition replace all rubber sealing rings.
10. Dip primary and secondary pistons and new sealing rings into brake liquid and apply a thin film brake liquid on openings for pistons in the main brake cylinder.
11. Establish a spring on knot of the secondary piston and, being careful and turning, establish the secondary piston to the canal of the main brake cylinder.
12. Check that the groove of the secondary piston is correctly established concerning the case of the main brake cylinder, then press the piston and fix it a pin.
13. Establish a spring on knot of the primary piston and, being careful and turning, establish the primary piston to the canal of the main brake cylinder.
14. Using a steel core, press the primary piston and establish a new sealing ring, a washer and a lock ring. Check that the lock ring was reliably established in a flute of the main brake cylinder.
15. Insert new fixing consolidations of a popolnitelny tank.

Installation

PERFORMANCE ORDER
1. Clear interfaced surfaces of the main brake cylinder and the vacuum amplifier of brakes and establish a new sealing ring on a back part of the main brake cylinder.
2. Establish the main brake cylinder on the vacuum amplifier of brakes. Thus the pusher of the vacuum amplifier of brakes should be established in an opening of the primary piston. Screw nuts of fastening of the main brake cylinder and tighten them the demanded moment.
3. Wipe brake tubes, establish them on the places in the main brake cylinder and fix connecting nuts, having tightened them the demanded moment.
4. Establish a popolnitelny tank of brake system on the main brake cylinder and connect to it a hose of supply of liquid to hydraulic system of coupling.
5. Fill in brake liquid in a popolnitelny tank of brake system and remove from brake system air.