Remove/check/install front axle brake pads

AR42.10-S-1600S

Remove/check/install front axle brake pads

09.10.2018

Model

636, 639

Modification notes

15.12.2015

Method extended

Operation step 13

26.09.2018

Brake lining wear limit

BE42.10-N-1001-11E

10

Brake fluid reservoir

10a

Cap

1

Electrical connector

2

Screw

3

Brake hose

31

Floating caliper

33

Floating brake caliper carrier

S10/1

Brake pad contact sensor, left front

S10/2

Brake pad contact sensor, right front

31

Floating caliper

31g

Brake lining

33

Floating brake caliper carrier

61

Brake disk

 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

 Danger

Risk of accident when commissioning the vehicle due to a lack of braking effect when the service brake is operated for the first time after repair work.

Before starting the engine, actuate brake pedal several times until pressure is built up and maintained in the brake system.

AS42.50-Z-0002-01A

Topical note

Brake fluid notes

AH42.50-P-0001-01A

Topical note

Notes on repairs to brake system

AH42.00-P-0003-01A

Topical note

Notes on self-locking nuts and bolts

AH00.00-N-0001-01A

 

Remove/install

1

Open engine hood and secure against falling down

2

Unscrew cap (10a) of brake fluid reservoir (10)

 Installation: Only correct the brake fluid level after actuating the brake pedal several times. The brake pads (31g) must make contact with the brake disks (61). Firm resistance should be noticeable at the brake pedal.

3

Remove front wheels

AR40.10-S-1100S

4

Disconnect electrical connection (1)

 Installation: Ensure electrical line is routed correctly.

5

Remove lower bolt (2) and swivel floating brake caliper (31) upward

 Installation:
When swiveling the floating brake caliper (31) downward, do not damage the protective boot of the pilot bushing.
The pilot bushing can otherwise corrode.

 Installation:
On vehicles with Brembo bake system, coat the inside of the cap of the bolt (2) with the assembly grease contained in the repair kit.
Otherwise, the bolt (2) may corrode.

 Installation: Replace bolt (2).

 Bolt, floating brake caliper to floating brake caliper carrier

*BA42.10-N-1002-03A

6

Remove brake pads (31g) from floating caliper carrier (33)

 Installation:
Do not apply any brake paste or assembly grease.
This can otherwise cause the brake system to malfunction.

 Installation: Install brake linings (31g) with left front brake pad contact sensor (S101) and right front brake pad contact sensor (S102) on the outside.



Check

7

Check brake pads (31g) and brake disks (61)

Topical note

Notes on evaluating brake disks

AH42.10-N-9406-07B

Brake disk

*BE42.10-N-1001-08B

Brake lining wear limit

*BE42.10-N-1001-11E

8

Check brake hoses (3)

If damaged or fractured



Replace brake hoses (3)

AR42.10-S-0013SV

9

Press back piston of floating brake caliper (31)


The dust boot may not protrude here.
The dust boot can otherwise be damaged.

 If the brake fluid level in the brake fluid reservoir (10) is too high, extract some brake fluid.
Commercially available devices/tools
Extraction bellows

 Resetting device

*000589524300

If piston is sluggish or dust boot damaged.



Replace floating brake caliper (31)

Remove/install front axle brake caliper

AR42.10-S-0070S

10

Remove sliding plates from brake linings (31g)

 The slide plates only have to be replaced if they exhibit damage.



Clean

11

Clean contact surfaces of brake linings (31g) on carrier for floating brake caliper (33) and on floating brake caliper (31)

 Brake caliper brush

*000589266800

12

Install in the reverse order



Check

13

Carry out brake test on the test stand



AP42.00-D-4290A

Check values for front axle brake disks

Number

Designation

Model 636.705/813

Model 639.601/603/605/701/703/705/711/713/811/813/815

BE42.10-N-1001-08B

Brake disk

Thickness when new

mm

28

28

Wear limit

mm

25

25

Lateral runout

mm

 0,01

 0,01

Flatness deviation

mm

 0,04

 0,04

Repair limit dimension

mm

–

-

Check values for brake caliper brake lining

Number

Designation

Model 636

Model 639

BE42.10-N-1001-11E

Brake lining wear limit

mm

3,5

3,5

 Front axle floating caliper

Number

Designation

Model 636.705/813

Model 639.601/603/605/701/703/705/711/713/811/813/815

BA42.10-N-1002-03A

Bolt, floating brake caliper to floating brake caliper carrier

ITT

Nm

–

–

Bosch

Nm

39

39

Brembo

Nm

–

34