Bleed clutch operating system

AR25.20-G-0070CC

Bleed clutch operating system

19.03.2020

Model

437.420/421/425/426/430/431/435/436 ## up to 262508

with code G48 (Electronic automated gearshift (EAS))

Model

437.465 up to 3/31/17

with code G48 (Electronic automated gearshift (EAS))

1

Brake fluid reservoir

2

Clutch pedal

2.1

Release lever

3

Vent valve

4

Clutch booster

5

Vent valve

6

Vent valve

7

Cover panel

B23

EAS clutch actuator

8

Vent valve

9

Vent valve

Y39

EAS protection valve

Y39y1

Protective preselect valve 1

Y39y2

Protection preselect valve 2

Y39y3

Clutch protection valve

 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

 Warning

Risk of injury. Moving parts can pinch, crush or, in extreme cases even sever extremities.

No parts of the body or limbs should be within the operating area of mechanical components when moving components.

AS00.00-Z-0009-01A

 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

Brake fluid notes

AH42.50-P-0001-01A

Notes on bleeding clutch operating system

AH25.20-N-0002-01BC

Prepare bleeding

1

Start engine and fill compressed-air system up to shutoff pressure.

2

Turn steering to right.

3

Switch off engine.

4

Open hood.

Model 437.42/43

AR88.40-G-1000C

 Model 437.465
See information from body manufacturer.

5

Unscrew cap from brake fluid reservoir (1).

6

Check that sieve is present in brake fluid reservoir (1).

If no sieve is present in brake fluid reservoir (1),



Retrofit sieve into brake fluid reservoir (1).

7

Screw breather connection onto brake fluid reservoir (1) and connect filling unit.



Brake fluids (DOT 4 plus)

BB00.40-P-0331-00A



000 588 01 82 00 Filling unit

WS25.00-P-0016B

 Note operator's manual for filling unit. The filling unit must be completely filled with brake fluid.

 Vent fitting

*000589032500

8

Remove cover panel (7) from frame at left.

9

Attach vent hose using a hose clamp to bleed valve (3) of clutch booster (4).

10

Operate release lever (2.1) and fold out clutch pedal (2).

11

Switch on ignition.

 Protective preselect valve 1 (Y39y1) on the EAS protection valve (Y39) is energized and the system switched to the pedal circuit.

Bleed pedal circuit

12

Switch on filling unit.

 Set bleeding pressure to a maximum of 2.7 bar. The bleeding pressure may not drop below 1.5 bar. The filling unit remains switched on during the entire bleeding procedure.

13

Open bleed valve (3) on clutch booster (4) and collect brake fluid in a container.

 While bleeding the clutch pedal (2) slowly and fully depress several times until new brake fluid escapes bubble-free. Each time after fully depressing, wait for 5 s.
Helper required.

14

Conduct bleeding process successively on bleed valve (5), then on bleed valve (6) and then on bleed valves (8, 9) of the EAS protection valve (Y39).

 Secure the bleed hose to each bleed valve (5, 6, 8, 9) using a hose clamp.
During the bleeding procedure, fully depress the clutch pedal (2) slowly several times until the brake fluid is discharged without bubbles. After the pedal returns to the top of its travel, wait 5 seconds before depressing it again.
Helper required.

 Bleed valve to protection valve

*BA25.20-N-1008-01I

Bleed automatic circuit

15

Switch off ignition and remove key.

16

Operate release lever (2.1) and fold in clutch pedal (2).

17

Switch on ignition.

 The clutch protection valve (Y39y3) on the EAS protection valve (Y39) is energized and the system switched to the automatic circuit.

18

Conduct bleeding procedures successively on bleed valves (3, 5), then on bleed valve (6) and then on bleed valves (8, 9).

 Secure the bleed hose to each bleed valve (3, 5, 6, 8, 9) using a hose clamp.
During the bleeding process, press the left button on the gearshift lever, push the gearshift lever forward and release again.
Repeat this process several times for each bleed valve (3, 5, 6, 8, 9) until the brake fluid is discharged free of bubbles. Wait 5 s between each procedure. Helper required.

19

Carry out bleeding processes in reverse order.

 Sequence of bleeding procedures:
First bleed at bleed valve (9) and then at bleed valves (8, 6, 5, 3).
Secure the bleed hose to each bleed valve (9, 8, 6, 5, 3) using a hose clamp.
Open bleed valves (9, 8, 6, 5, 3) briefly only (approx. 2 s) and then close again.

 Bleed valve to protection valve

*BA25.20-N-1008-01I

20

Switch off filling unit.

21

On brake fluid reservoir (1), detach connector coupling of filling unit from breather connection.

 Clutch operation is hereby set to the unpressurized state.



Check

22

With the ignition switched on, engage a gear and run a function test in automatic mode.

 The gear indicator may flash on and off.

If it is not possible to engage a gear,



Fit connector coupling to breather connection and fully bleed the hydraulic system of the clutch again; repeat operation steps 9 to 21.

23

Start engine and fill compressed-air system up to shutoff pressure.

24

Switch off engine.

25

Check emergency clutch operation.



AP25.20-G-2956CC

26

Remove filling unit.

 Note operator's manual for filling unit.

27

Remove breather connection and tighten cap of brake fluid reservoir (1).

28

Check fluid level in brake fluid reservoir (1).



AP25.20-G-2910C

29

Close hood.

Model 437.42/43

AR88.40-G-1000C

 Model 437.465
See information from body manufacturer.

30

Install cover panel (7).

31

Switch on ignition, apply parking brake with the engine switched off and engage gear.

32

Operate release lever (2.1) and fold out clutch pedal (2).

33

Fully depress clutch pedal (2) slowly until clutch pedal (2) pushes back at end position; hold pedal at this position.

34

Shift gearshift lever to "Neutral", switch off ignition and release clutch pedal (2).

35

Operate release lever (2.1) and fold in clutch pedal (2).

36

Perform major learning process.

AR54.21-G-0007-02CC

 Clutch operating system

Number

Designation

Engine 900.91/92, 902.92/93, 904.92/95, 906.935/95, 924.91/92/93, 926.96

BA25.20-N-1008-01I

Bleed valve to protection valve

Nm

15