BMW 5 Series E39

since 1996-2001 release

Repair and operation of the car



BMW E39
+ Introduction
+ Maintenance instruction
+ Current leaving and service
+ Engine
+ Cooling systems, heating
+ Power supply system and release
+ Engine electric equipment
+ Manual transmission
+ Automatic transmission
+ Coupling and power shafts
- Brake system
   Anti-blocking system
   Removal and installation of front brake shoes
   Removal and installation of a brake disk / support of a forward brake
   Removal and installation of back brake shoes
   Removal and installation of back brake supports
   Removal and installation of a brake disk of back wheels
   Measurement of thickness of a brake disk
   Brake fluid
   Removal of air from the brake system
   Replacement of brake pipelines
   Replacement of a forward brake hose
   Check of the vacuum amplifier of a brake
   Removal and installation of brake shoes of the parking brake
   Adjustment of the parking brake
   Removal and installation of the lever of the parking brake
   Removal and installation of a cable of the parking brake
   Check and replacement of the switch of a stoplight
+ Suspension bracket and steering
+ Body
+ Onboard electric equipment
+ Schemes of electric equipment
+ System of onboard diagnostics





Brake system

Specifications

Separate characteristics are provided also in the text of the Head and in case of obligation of their performance are highlighted in bold type


Design

Disk on all wheels. Additional drums of the parking brake on back wheels
The brake amplifier at cars with the petrol engine.
Double-circuit hydraulic system: one contour of forward brakes, the second - back.
Distribution of effort of braking is carried out by anti-blocking system (ABS)


Characteristic

Value

Type of brake fluid

DOT 4

Blocks of a disk brake: the minimum thickness without back plate

3.0 mm

Blocks of a drum brake: minimum thickness

1.5 mm

Brake disk forward:

 

      •  minimum thickness

20.4 mm

      •  diameter

296.0 mm

Brake disk back: minimum thickness

 

      •  continuous disk

8.4 mm

      •  the ventilated disk

18.4 mm

      •  diameter

298.0 mm

Amount of processing and admissions:

 

      •  the maximum size of processing on the party

0.8 mm

      •  the admission on thickness

0.02 mm

      •  maximum face beating
              ••  established
              ••  removed


0.2 mm
0.05 mm

Parking brake:

 

      •  diameter of the brake drum

185.0 mm

      •  maximum radial beating

0.1 mm

Efforts of tightening of threaded connections

The moments of an inhaling of fixture are given in the text of the Head and on some illyustratsiyakh*.
* The moments of an inhaling highlighted in the text in bold type are subject to exact observance; the efforts which are not highlighted in bold type are given only approximately.

General information

The brake system consists of the main brake cylinder, the amplifier of a brake and disk brakes of forward and back wheels. The hydraulic system of brakes has two contours: one contour influences forward brakes, the second back. It provides a possibility of braking of the car in case of failure of one of contours, for example owing to depressurization of system, thanks to action of another. Pressure of brake fluid is created in the dual main brake cylinder as a result of pressing of a pedal of a brake. The regulator of brake effort in system is absent since distribution of effort of braking is carried out by anti-blocking system (ABS).

The tank of brake fluid is in a motive compartment on the left side under the case of the filter of clean air. The tank supplies system of braking with liquid.

The vacuum amplifier of a brake at cars with the petrol engine accumulates a part of the air which is soaked up by the engine. The effort of a pedal of a brake via the valve amplifies at the expense of the available vacuum. At the diesel engine of vacuum on absorption is not present. Therefore here vacuum for strengthening of braking is created by the vacuum pump located on a head of cylinders.

All disk brakes are equipped with rigid supports. When braking brake shoes nestle on a disk the piston.

Supports are made of alloy of light metal. It provides good heat removal, formed in the course of braking that interferes with emergence of so-called "feding". "Feding" represents easing of efficiency of braking owing to strong heating of brakes.

On left forward and right back brakes sensors of wear of brake shoes are installed.

The parking brake influences back wheels and is set in motion through a cable. As the disk brake as parking has certain shortcomings, on back wheels two drum brakes which are built in brake disks are in addition established. The drive of the parking brake is carried out from the lever.

When cleaning the brake system brake dust is formed. This dust constitutes health hazard. Therefore when cleaning the brake system you watch that brake dust did not get into airways.

Brake shoes are subject to control from bodies of technical supervision. Besides, they are intended for use in concrete model of the car. It is recommended to apply original brake shoes.

Work with the brake system demands special purity and exact observance of instructions. In the absence of necessary experience it is expedient to address on HUNDRED.

The fulfilled brake fluid needs to be handed over in special point of utilization. To throw out it with other household waste it is not allowed.

At movement along wet roads it is necessary to press periodically a brake pedal for drying of disk brakes. In the course of rotation of a wheel moisture under the influence of centrifugal force is dumped from brake disks, but there is a film of silicone, a rubber attrition product, lubricant and the other pollution reducing efficiency of operation of brakes.