ar2520b0300a

Clutch servo unit removal and installation

Type ar · topic 25.20 · version 0103 · 2018-10-01

Applies to: Model 634 with engine 457.916/927/932

Where it sits

Function group 2 Chassis › 25 Clutch › 25.20 Clutch actuation — Series 634

EinPAS 17 Drivetrain/axle › 17.15 Clutch › 17.15.5 Clutch operation — Series 634

Also applies to engines/gearboxes: 457 916, 457 927, 457 932

AR25.20-B-0300A

Clutch servo unit removal and installation

01.10.2018

Model

634 with engine 457.916/927/932

Clutch servo unit removal and installation

1

Clutch booster

2

Clutch actuation hydraulic line

3

Pneumatic line of the clutch booster

4

Clutch wear indicator sensor

T25.20-0025-03

Remove/install

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

1

Release pressure from secondary pneumatic circuit

Brake fluid notes

AH42.50-B-0001-01A

To release pressure, open secondary pneumatic circuit reservoir bleeder valve.

2

Remove the lining under the engine compartment

Carry out only the work steps necessary for the removal of the lining under the gearbox.

3

Loosen the electrical connector in the clutch wear indicator sensor (4)

Installation: If a new clutch booster is installed (1) or clutch parts are replaced:

The clutch return travel must be stored in the vehicle control unit (FR).

4

Disconnect hydraulic line (2) from the clutch booster (1)

Catch the running off hydraulic fluid in a suitable container.

5

Disconnect the pneumatic line (3) from the clutch booster (1)

Installation: Replace sealing rings.

6

Loosen the bolts and remove the clutch booster (1)

.

.Clutch booster attachment bolt

*BA25.20-B-1002-01H

7

Install on the reverse order

8

Bleed the clutch system

Clutch drive

Number

Designation

457.916/932 engine with WGTZ 430 clutch

BA25.20-B-1002-01H

Clutch booster attachment bolt

M8

Nm

20...22

M10

Nm

54...62

Referenced documents