Remove/install front axle axle modulator

AR42.25-W-3000H

Remove/install front axle axle modulator

10.12.2019

Model

963, 964

with code Z1G (Electronic Brake Control (EBS) from Knorr)

except code Z1H (Electronic Brake Control (EBS) from Wabco)

1

Cover

2

Bracket

A20a

Front axle axle modulator

33.07

3/2-way valve for auxiliary braking effect

 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

Topical note

Notes on self-locking nuts and bolts

AH00.00-N-0001-01A

Notes on checking axle modulator before replacement

AH42.25-W-0001-01H

 

Remove/install

1

Secure vehicle to prevent it moving away.

2

Drain compressed air system completely.

3

Switch off ignition.

4

Remove cover (1) and detach electrical connectors from front axle modulator (A20a).

 Installation: Observe color coding of electrical connectors.

5

Mark all compressed air connectors as per labeling on front axle modulator (A20a) and remove.

AR42.10-W-0900H

 Installation: Observe markings.

6

Release front axle modulator (A20a) at holder (2).

 Screw/bolt, axle modulator on front axle (Knorr) to bracket

*BA42.25-N-1002-01B

7

Release 3/2-way valve for auxiliary braking effect (33.07) at holder (2).

 Nut, 3/2-way valve for secondary braking to bracket

*BA42.25-N-1005-01B

8

Remove holder (2) from frame.

 Bracket, axle modulator on front axle to frame

*BA42.25-N-1003-01B

9

Remove front axle modulator (A20a) together with 3/2-way valve for auxiliary braking effect (33.07) from holder (2).

10

Remove front axle modulator (A20a) from 3/2-way valve for auxiliary braking effect (33.07).

 Installation: Install new O-ring.

 Threaded fitting between axle modulator on front axle and shuttle valve/valve for auxiliary braking effect

*BA42.25-N-1004-01B

11

Install in the reverse order.



Check

12

Start engine and completely fill compressed-air system.

13

Switch off engine.

14

Operate brake pedal and fix in place using brake pedal jack.

 Brake pedal jack

*000589183100

15

Check compressed-air connections at front axle modulator (A20a) for leak tightness.

Leak detection spray

*BR00.45-Z-1002-03A

16

Remove brake pedal jack.

 Electropneumatic brake (EPB)

Number

Designation

Model 963, 964

BA42.25-N-1002-01B

Screw/bolt, axle modulator on front axle (Knorr) to bracket

Nm

18

 Electropneumatic brake (EPB)

Number

Designation

Model 963, 964

BA42.25-N-1003-01B

Bracket, axle modulator on front axle to frame

M10

Nm

50

M12

Nm

100

 Electropneumatic brake (EPB)

Number

Designation

Model 963, 964

BA42.25-N-1004-01B

Threaded fitting between axle modulator on front axle and shuttle valve/valve for auxiliary braking effect

Nm

14

 Electropneumatic brake (EPB)

Number

Designation

Model 963, 964

BA42.25-N-1005-01B

Nut, 3/2-way valve for secondary braking to bracket

Nm

18

Repair materials

Number

Designation

Order number

BR00.45-Z-1002-03A

Leak detection spray

Christof Fischer GmbH
www.kaeltefischer.de