Test brake system with pressure tester for leaks

AR42.10-P-0015MFA

Test brake system with pressure tester for leaks

06.03.2020

Model

118, 177, 247

1

Brake fluid reservoir

2

Brake caliper

3

Tester

4

Brake pedal jack

5

Brake booster

 Warning

Risk of accident from vehicle starting off by itself when engine running. Risk of injury (bruises and burns) resulting from working on the engine while it is being started or when it is running.

Secure vehicle to prevent it from starting off by itself. Wear closed and snug-fitting work clothes. Do not touch hot or rotating parts.

AS00.00-Z-0005-01A

 Caution

Risk of poisoning from swallowing brake fluid. Risk of injury from skin and eye contact with brake fluid

Only pour brake fluid into suitable and appropriately marked containers. Wear protective clothing and eye protection when handling brake fluid.

AS42.50-Z-0001-01A

Topical note

Notes on repairs to brake system

AH42.00-P-0003-01A

Topical note

Notes on externally invisible brake fluid loss

AH42.10-P-9406-02A

Topical note

Brake fluid notes

AH42.50-P-0001-01A



Check

1

Clean area around cap of brake fluid reservoir (1).

Assembly cleaner

*BR00.45-Z-1028-04A

2

Unscrew cap of brake fluid reservoir (1).

3

Connect filling unit to brake fluid reservoir (1).



000 588 01 82 00 Filling unit

WS25.00-P-0016B



Brake fluids (DOT 4 plus)

BB00.40-P-0331-00A



General brake fluid

BB00.40-P-0330-01A

 Observe manufacturer's operating instructions.

4

Raise vehicle.

AR00.60-P-1006A

5

Remove vent screw from front left brake caliper (2) and connect test equipment (3).



000 588 07 21 00 Test equipment

WS42.00-P-0014B


Do not use test equipment (3) for hydraulic oil systems on systems with brake fluid.
Otherwise, the brake fluid will be mixed with mineral oil, which can cause brake failure.

6

Bleed test equipment (3).

 Observe manufacturer's operating instructions.

7

Start engine and run.

8

Depress brake pedal and insert brake pedal jack (4) with adapter between brake pedal and driver's seat.

 Cover up brake pedal and driver's seat in brake pedal jack (4) system area.

 Brake pedal jack

*000589183100

 Adapter for brake pedal winch

*211589003100

9

Read off and note brake pressure on high-pressure manometer of test equipment (3).

10

Read off brake pressure again on high-pressure manometer of test equipment (3) after the specified test period and compare against previously-noted value.

Check values for leak test

*BE42.10-P-1001-19A

If the brake pressure loss is too high.



Determine cause and replace defective component parts.

11

Switch off engine and remove brake pedal jack (4) with adapter.

12

Reduce vacuum in brake booster (5) by depressing brake pedal several times.

13

Depress brake pedal and insert brake pedal jack (4) with adapter between brake pedal and driver's seat.

 Brake pedal jack

*000589183100

 Adapter for brake pedal winch

*211589003100

14

Slowly turn back brake pedal jack (4) until the low-pressure manometer of the test equipment (3) displays the specified brake pressure.

Check values for leak test

*BE42.10-P-1001-19A

15

Read off brake pressure on low-pressure manometer of test equipment (3) after the specified test period.

Check values for leak test

*BE42.10-P-1001-19A

If a drop in brake pressure is detected,



determine leakage in brake system and replace defective component parts.

16

Remove brake pedal jack (4) and adapter.

17

Disconnect test equipment (3) from brake caliper (2) and screw vent screw all the way into brake caliper (2).

18

Bleed front left brake caliper (2).

AR42.10-P-0010-02MFA

Topical note

Notes on handling, transport and storage of composite brake disks

AH42.10-P-9406-12LF



000 588 01 82 00 Filling unit

WS25.00-P-0016B

 Bleed screw at brake caliper

*BA42.10-P-1004-10ZA

19

Disconnect filling unit from brake fluid reservoir (1).



000 588 01 82 00 Filling unit

WS25.00-P-0016B

20

Correct fluid level in brake fluid reservoir (1).



AP42.10-P-4210D

21

Seal brake fluid reservoir (1) with cap.

22

Install cover over brake fluid reservoir (1).

23

Lower vehicle.

AR00.60-P-1006A

Hydraulic brake system

Number

Designation

Model 118

Model 177, 247

BE42.10-P-1001-19A

Check values for leak test

High-pressure test

Test period

min

5

5

Brake pressure loss

%

5

5

Low-pressure test

Brake pressure

bar

3

3

Test period

min

2

2

Brake pressure loss

bar

0

0

 Front axle brake caliper

Number

Designation

Model 118

Model 177

BA42.10-P-1004-10ZA

Bleed screw at brake caliper

M10

Nm

18

18

 Front axle brake caliper

Number

Designation

Model 247

BA42.10-P-1004-10ZA

Bleed screw at brake caliper

M10

Nm

18

Repair materials

Number

Designation

Order number

BR00.45-Z-1028-04A

Assembly cleaner

A 000 986 56 01