Remove/check/install front axle brake pads

AR42.10-P-1600MCC

Remove/check/install front axle brake pads

09.10.2018

Model

451.3/4

Modification notes

26.09.2018

Brake lining thickness

BE42.10-P-1001-05E

1

Brake caliper

2

Screw

3

Springs

4

Guide pin

5

Caliper support

6

Brake pads

7

Dust boot

8

Brake piston

9

Wear indicator

10

Brake piston resetting device

4

Guide pin

11

Bellows

5

Caliper support

12

Lip



Remove

 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

Brake fluid notes

AH42.50-P-0001-01A

Topical note

Notes on repairs to brake system

AH42.00-P-0003-01A

1

Remove left or right front wheel

AR40.10-P-1100MCC

2

Counterhold upper guide pin (4) using a suitable open end wrench and unscrew bolt (2) on brake caliper (1)

3

Fold brake caliper (1) upwards and remove brake pads (6)


Make sure that the brake pedal is no longer operated after removing the brake pads (6).
Otherwise the brake piston (8) may be pushed out of the brake caliper (1).

 Observe installation position of brake pad (6) with wear indicator (9).

4

Press back the brake piston (8) using the brake piston pusher tool (10)

 When the brake piston (8) is pushed back the fluid level in the brake fluid reservoir rises. Ensure that the brake fluid reservoir does not overflow. It must be possible to move the brake piston (8) easily.

 Brake piston pusher tool

*450589023700



Check

5

Check dust boot (7) for leaktightness

If dust boot (7) is damaged, the brake caliper (1) has to be replaced.



Remove/install front axle brake caliper

AR42.10-P-0070MCC

6

Check wear and condition of brake pads (6) as well as the brake disks

Brake lining thickness

*BE42.10-P-1001-05E

Brake disk thickness

*BE42.10-P-1001-08E

 Vernier caliper

*450589011900

7

Check guide pin (4) ease of movement

If the guide pins (4) get hooked or if they are sluggish, the brake caliper (1) has to be replaced.



Remove/install front axle brake caliper

AR42.10-P-0070MCC

8

Check bellows (11) for damage

 Damaged bellows (11) should be replaced.

 Twist the respective boot (11) with the fingers in order to ensure that sealing lip (12) seats correctly in the slot on the corresponding guide pin (4).



Install

9

Clean contact surfaces (arrows) on the brake pads (6) and brake caliper support (5) and coat with grease


Grease must not come into contact with the friction surfaces of the brake pads (6) and the brake disk.
Otherwise the braking effect will be impaired.

Molykote 111 grease

*BR00.45-Z-1070-06A

10

Install brake pads (6) and fold brake caliper (1) downwards

 When fastening the brake caliper (1) ensure that the springs (3) of the brake pads (6) are clamped under the brake caliper (1).

 Observe installation position of brake pad (6) with wear indicator (9).

11

Counterhold upper guide pin (4) using a suitable open end wrench and tighten bolt (2) on brake caliper (1)

 Bolt, brake caliper to brake caliper support

*BA42.10-P-1001-10A

12

Mount left or right front wheel

AR40.10-P-1100MCC

 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

13

Depress the brake pedal several times until the brake pads (6) contact the brake disk

 A firm resistance must be noticeable at the brake pedal.

14

Check brake system for leaks

AR42.10-P-0100-01MCC

Check values for front brake lining

Number

Designation

Model 451.3/4

BE42.10-P-1001-05E

Brake lining thickness

New (with pad backing plate)

mm

15

Wear limit (without pad backing plate) for maintenance service

mm

2

Wear limit (with pad backing plate) for maintenance service

mm

7,7

Response of wear indicator (with pad backing plate)

mm

7,7

Check values for front axle brake disks

Number

Designation

Model 451.3/4

BE42.10-P-1001-08E

Brake disk thickness

New

mm

9,7

Wear limit

mm

8

 Front axle floating caliper

Number

Designation

Model 451.3/4

BA42.10-P-1001-10A

Bolt, brake caliper to brake caliper support

Nm

30

Repair materials

Number

Designation

Order number

BR00.45-Z-1070-06A

Molykote 111 grease

Q0014759V000000000