Description, removal and installation of the vacuum hydraulic booster of brake system. BMW the 5th E28/E34 series (from 1981 to 1993 of release)
автомобили с японских
Repair of BMW E28 and series E34 from 1981 to 1993
1. Cars of the BMW brand of 5-series
2. Engine
3. Cooling system
4. Power supply system
5. Ignition system
6. Control systems of the engine and decrease in toxicity of the fulfilled gases
7. System of production of the fulfilled gases
8. Coupling
9. Manual box of gear shifting (RKPP) and automatic transmission (AT)
10. Transmission line
11. Steering and suspension bracket
12. Brake system
12.1. General information
12.2. General information on anti-blocking brake system
12.3. Replacement of blocks of disk brake mechanisms
12.4. Removal, major maintenance and installation of a support of the disk brake mechanism
12.5. Survey, removal and installation of a brake disk
12.6. Replacement of boots of drums of brake mechanisms
12.7. Removal and installation of the main brake cylinder
12.8. Condition check, removal and installation of the vacuum amplifier of brakes
12.9. Description, removal and installation of the vacuum hydraulic booster of brake system
12.10. Replacement of a cable (cables) of a drive of the parking brake
12.11. Adjustment of the parking brake
12.12. Condition check, removal and installation of assembly of the parking brake
12.13. Adjustment of a pedal of a brake
12.14. Check and adjustment of the switch of a stoplight
12.15. Survey and replacement of brake lines and hoses of hydraulic system of brakes
12.16. Pumping of hydraulic system of brakes
12.17. Diagnostics of malfunctions of brake system
13. Body
14. Control body sizes
15. Heater and air conditioner
16. System of onboard electric equipment
17. Routine maintenance of the car
18. Size table and adjusting data
19. Schematic electric circuits
20. Governing bodies and operation receptions
21. System of onboard diagnostics - a principle of functioning and codes of malfunctions
 








12-9-opisanie-snyatie-i-ustanovka-vakuumnogo-gidrousilitelya-tormoznojj-sistemy.html

12.9. Description, removal and installation of the vacuum hydraulic booster of brake system

Brake liquid is poisonous. It also strongly dissolves paint. See. The prevention at the beginning of the Section Pumping of hydraulic system of brakes.

Description

On the E28 models (in retro style) the vacuum hydraulic booster is used. The block of the amplifier located between a pedal of a brake (for models with left foreign management) or the lever of a cross-section shaft (for models with right-hand management) and the main cylinder, is put in action by the pressure of liquid made by the steering pump with hydrostrengthening. At the switched-on engine the steering pump submits pressure upon the pressure regulator/accumulator. The regulator/accumulator accumulates and regulates pressure in the vacuum hydraulic booster. By pressing a brake pedal pressure in the amplifier helps to put in action the main cylinder, reducing necessary effort of pressure to a pedal.

The vacuum hydraulic booster is not subject to major maintenance; in default it is necessary to replace it. Check of work of system demands special adaptations therefore even diagnostics of malfunctions is not included into competence of the house mechanic. If the system refuses, send her to dealer office of service or other automobile repair shop.

Removal and installation

 PERFORMANCE ORDER

  1. At the switched-off engine discharge the hydraulic accumulator, having squeezed out a pedal of a brake of 20 or more times.
  2. Remove the main cylinder (see. Section Removal and installation of the main brake cylinder).
  3. Clear area round shtutserny connections of inlet and returnable lines, then disunite them. Stop up tubes to prevent dirt hit in system and leakage of liquid.

Even the tiny part of dirt can damage the amplifier therefore be especially careful, do not allow dirt hit in system at the disconnected tubes.

  1. Working in passenger office, remove the bottom left panels of a covering over a brake pedal (for models with left foreign management) or a ware box and a covering (for models with right-hand management). On models with left foreign management also disconnect a returnable spring of a pedal.
  2. Take a fixing clip and disconnect a pusher from a pedal of a brake or the lever of a cross-section shaft.
  3. Give four fixing nuts and remove the vacuum amplifier.
  4. Installation repeats removal procedure upside-down. Tighten shtutserny connections of hydraulic lines with demanded effort.

Do not torture to tighten these connections without the aid of a key. If they are bad for tightening, they can escape that will affect system work; if to draw them, it is possible to damage a carving that also will lead to leak. For the correct tightening of these connections you will need a special cutting cap nozzle on your wrench.

  1. Upon termination of work pump over hydraulic system of brakes (The section Pumping of hydraulic system of brakes) and adjust a course of a pedal of a brake and the stoplight switch (see. Section Adjustment of a pedal of a brake).


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12.8. Condition check, removal and installation of the vacuum amplifier of brakes
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12.10. Replacement of a cable (cables) of a drive of the parking brake