Checking brake booster

AR43.10-P-0325I

Checking brake booster

10.11.11

11.8.05

Bleed screw on rear axle fixed brake caliper

Model 215.379



Checking

1

Operate brake pedal several times until vacuum in brake booster (16) is reduced

2

Connect testing unit (030) to brake booster

 Measuring connection (031) for checking check valve (17) or brake booster (16).

AR43.10-P-0024-01I

 Vacuum tester

*201589132100

 Test connection

*168589086300

Test values for brake booster

*BE43.10-P-1001-01A

Test values for brake booster

*BE43.10-P-1002-01A

3

Connect pressure tester (051) with connection fitting to brake caliper

Pressure tester

gotis://B_42/43.2_03.0

 After testing, only bleed the brake caliper to which the pressure tester was connected.

 Front axle bleed screw

*BA42.10-P-1002-10G

 Rear axle bleed screw

*BA42.10-P-1002-12G

4

Connect pedal force measuring instrument (060) at brake pedal

Pedal force meter
gotis://B_42/43.1_03.0

5

Start engine and create a vacuum of 0.75 to 0.80 bar by accelerating and then suddenly releasing the accelerator pedal

 If the vacuum is considerably lower or if the vacuum drops immediately,

the O-ring between the brake booster and master brake cylinder may be damaged or the non-return valve in the vacuum line may be defective:

Checking check valve

AR43.10-P-0023I

Remove/install master brake cylinder, install new O-ring

AR42.10-P-0300I

6

Apply specified force to the brake pedal and read line pressure

To cover measurement errors as far as possible (wrong force on brake pedal, wrong vacuum) and measurement scatter of the gauges, a tolerance of 10 bar on the specified value is permissible.

*BE43.10-P-1003-01A

 The measured value must be within the value range.

7

Disconnect testing unit (030) from brake booster

 Vacuum tester

*201589132100

 Test connection

*168589086300

8

Disconnect pressure tester (051) with connection fitting from brake caliper

Pressure tester

 Test connection

*168589086300

9

Remove pedal force meter (060) from brake pedal

10

Bleed brake system

Pedal force meter
gotis://B_42/43.1_03.0

AR42.10-P-0010I

Number

Designation

Model
215

Model
220

BE43.10-P-1001-01A

Brake booster dia.

-

mm

203/228,6

203/228,6

-

inch

8/9

8/9

BE43.10-P-1002-01A

Boost factor

6,3

6,3

BE43.10-P-1003-01A

Brake pipe line pressure

Intake pipe vacuum

Force on brake pedal

50 N

bar

22...30

22...30

0.75...0.8 bar

100 N

bar

42...52

42...52

150 N

bar

60...70

60...70

200 N

bar

80...95

80...95

250 N

bar

100...120

100...120

Number

Designation

Model
215

BA42.10-P-1002-10G

Bleed screw to brake caliper

Nm

7

Number

Designation

Model
215
except
215.374

Model
215.374

BA42.10-P-1002-12G

Bleed screw to brake caliper

Nm

7

14