Checking brake booster

AR43.10-P-0325A

Checking brake booster

10.11.11

19.10.00

Value changed from 4 to 7 Nm

Value changed to BA42.10-P-1002-03A on model 202.033/093, 208.374, 210.072 with code 957 (E50 AMG),
210.074/274



Checking

1

Press brake pedal several times until vacuum in brake booster is reduced

AR43.10-P-0024-01A

2

Disconnect testing unit at brake booster

AR43.10-P-0024-01A

 Vacuum tester

*201589132100

 Test connection, with connector on brake booster

*168589086300



Measurement connection for checking non-return valve or brake booster

With bolted connection on brake booster

WF58.50-P-4310-01A



*BA43.10-P-1001-01A

3

Connect, disconnect pressure tester (051) to connection fitting at brake caliper

Pressure tester

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

 Brake caliper

*BA42.10-P-1002-10I

 Brake caliper

*BA42.10-P-1002-10K

 Brake caliper

*BA42.10-P-1002-10D

 Brake caliper

*BA42.10-P-1002-10P

 Brake caliper

*BA42.10-P-1002-10F

4

Connect, remove pedal force measuring instrument (060) at brake pedal

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

5

Start engine and by depressing and suddenly releasing the accelerator pedal produce a vacuum of 0.75 - 0.80 bar

*BE43.10-P-1001-01A

*BE43.10-P-1002-01A

 If only a basically lower vacuum is reached or the vacuum drops again immediately, the O-ring between the brake booster and tandem master brake cylinder may be damaged or the check valve in the vacuum line may be defective: 

*BE43.10-P-1003-01A

Checking check valve

AR43.10-P-0023A

Vehicles with diesel engine - check vacuum pump: 

Model 202 with engine 601

ra07016010160x

Model 202 with engine 604, 605

Model 140 with engine 603

ra07016021843x

6

Supply brake pedal with specified force and read line pressure (see line pressure table)

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.

7

Bleed brake system

AR42.10-P-0010A

Number

Designation

Model
129.05/06
(ATE T52/4A 225210 or Lucas LSC 115)

Model
129.076
(ATE T52/4A 225210)

BE43.10-P-1001-01A

Brake booster dia.

-

mm

203/228,6

203/228,6

-

inches

8/9

8/9

BE43.10-P-1002-01A

Boost factor

5,6

5,6

BE43.10-P-1003-01A

Brake pipe line pressure

Intake pipe vacuum

Force on brake pedal

50 N

bar

14...25

14...25

0.75...0.8 bar

100 N

bar

35...45

35...45

150 N

bar

53 to 63

53 to 63

200 N

bar

71...81

71...81

250 N

bar

87...98

87...98

Number

Designation

Model
140.02/03/1
(ATE T52/4A 225210 or Lucas LSC 115)

Model Series
140.04/05/06/07 (ATE T52/ 4A 255225)

BE43.10-P-1001-01A

Brake booster dia.

-

mm

203/228,6

228.6/254

-

inches

8/9

9/10

BE43.10-P-1002-01A

Boost factor

5,6

6,85

BE43.10-P-1003-01A

Brake pipe line pressure

Intake pipe vacuum

Force on brake pedal

50 N

bar

14...25

13...25

0.75...0.8 bar

100 N

bar

35...45

35...47

150 N

bar

53 to 63

57...69

200 N

bar

71...81

78...92

250 N

bar

87...98

95...105

Number

Designation

Model 170.435/444/445/447/449/465/466

Model
202.018 to 9/93 and
model 202.120/ 121/122/125 to 04/94
(Lucas LSC 65 or Bendix Isovac dia. 225)

BE43.10-P-1001-01A

Brake booster dia.

-

mm

254

228,6

-

inches

10

9

BE43.10-P-1002-01A

Boost factor

4.5

3.85

BE43.10-P-1003-01A

Brake pipe line pressure

Intake pipe vacuum

Force on brake pedal

50 N

bar

13...23

7...15

0.75...0.8 bar

100 N

bar

32...44

26...38

150 N

bar

48...62

43...58

200 N

bar

62...78

62...75

250 N

bar

75...91

78...88

Number

Designation

Models
202.02/078/08/ 128/13/18/19
Model 202.018 as of
10/93
Models 202.120/121/
122/ 125 as of 05/94
(ATE T52/4A/255
or Lucas LSC 80)

Model
208.335/344/
345/347/348/
365/435/444/
445/447/448/
465

BE43.10-P-1001-01A

Brake booster dia.

-

mm

254

254

-

inches

10

10

BE43.10-P-1002-01A

Boost factor

4.5

4.5

BE43.10-P-1003-01A

Brake pipe line pressure

Intake pipe vacuum

Force on brake pedal

50 N

bar

13...23

13...23

0.75...0.8 bar

100 N

bar

32...44

32...44

150 N

bar

48...62

48...62

200 N

bar

62...78

62...78

250 N

bar

75...91

75...91

Number

Designation

Model
208.370/470

Model
210.003/004/
006/010/017/020/035/037/206/
210/235/237,
210.217 up to 01/97 (Teves), 210.061/261 without ESP

BE43.10-P-1001-01A

Brake booster dia.

-

mm

203/228,6

254

-

inches

8/9

10

BE43.10-P-1002-01A

Boost factor

5.6

5.0

BE43.10-P-1003-01A

Brake pipe line pressure

Intake pipe vacuum

Force on brake pedal

50 N

bar

8...18

15...25

0.75...0.8 bar

100 N

bar

33...40

38...50

150 N

bar

52...61

57...70

200 N

bar

68...79

72...83

250 N

bar

82...95

82...91

Number

Designation

Model
210.015/016/025/
026/045/053/055/063/
065/070/072/081/082/
210/215/216/225/226/
245/265/270/272/281/
282/606/610/617/663,
210.217 from 01/97 (Teves), 202.033/093,
210.074/274, 210.061/261 with ESP

BE43.10-P-1001-01A

Brake booster dia.

-

mm

203/228,6

-

inches

8/9

BE43.10-P-1002-01A

Boost factor

5.6

BE43.10-P-1003-01A

Brake pipe line pressure

Intake pipe vacuum

Force on brake pedal

50 N

bar

8...18

0.75...0.8 bar

100 N

bar

33...40

150 N

bar

52...61

200 N

bar

68...79

250 N

bar

82...95

Number

Designation

Model
129

Model
140 without special protection

Model
140 with
special protection

BA42.10-P-1002-10I

Bleed screw to brake caliper

Nm

7

7

7

Number

Designation

Model
202.018/020/
022/023/033/
078/080/081/
083/087/093/
120/121/122/
125/133/134/
180/182/193/
194,
Model
202.028
up to 08/95

Model
202.024/025/
026/029/082/
085/086/088/
089/128/188,
Model
202.028
as of 09/95

BA42.10-P-1002-10K

Bleed screw to brake caliper

Nm

7

7

Number

Designation

Model
170

BA42.10-P-1002-10P

Bleed screw to brake caliper

Nm

7

Number

Designation

Model
208

BA42.10-P-1002-10D

Bleed screw to brake caliper

Nm

7

Number

Designation

Model
210

BA42.10-P-1002-10F

Bleed screw to brake caliper

M8

Nm

7

Number

Designation

Model 129 up to 09/89

Model 129 as of 10/89

Model 140

BA43.10-P-1001-01A

Vacuum line to brake booster

Nm

30

30

30

Number

Designation

Model 170

Model 202

Model 208

Model 210

BA43.10-P-1001-01A

Vacuum line to brake booster

Nm

-

30

-

30