Remove/install valve springs and/or valve stem seals

AR05.30-S-3500SE

Remove/install valve springs and/or valve stem seals

17.05.2018

Engine

642 in model 470, 471

Engine

642 in model 639

Engine

642.896/898/992/993 in model 906

1

Connector

4

Upper valve spring retainer

7

Magnetic pin

2

Cylinder leakage tester

5

Valve spring

8

Valve stem seal

3

Valve assembly tool

6

Valve keeper

1

Connector

8

Valve stem seal

10

Pliers

2

Cylinder leakage tester

9

Drift

Topical note

Notes on avoiding damage through contamination and foreign objects

AH00.00-P-5000-01A

 

Remove/install

1

Remove the hydraulic valve clearance compensating element of the cylinder to be machined.

Model 470, 471

AR05.00-S-2013PS

Model 639, 906

AR05.00-S-2011SE

2

Have a help hold the timing chain up, rotate the engine on the vibration damper in the engine's direction of rotation and place the piston of the cylinder to be machined onto the TDC marking.

Model 470, 471, 639, 906

Model 470, 471

AR01.00-S-0100PS

Model 639

AR01.00-S-0100SE


Hold the timing chain up while rotating the engine.
Otherwise, the timing chain can get stuck while rotating and/or alter the times.

3

Remove the check valve, connect a commercially available cylinder leak test device (2) to the cylinder to be machined and apply a pressure of approx. 50 Pa to the cylinder to be machined.

 Connect adapter "R1/4" from the compression pressure recorder set with the connector (1) and insert connector (1) into the injector bore. The connector (1) is secured using the original clamping claw.

 Compression tester

*001589782100

 Connector

*611589006300

4

Push assembly tool valves (3) together, screw in retaining fork at edge of cylinder head into the thread and fit thrust piece vertically on the upper valve spring retainer (4).

 Valve assembly tools kit

*111589256100

 Depressor

*640589006100

5

Press together valve spring (5) with valves assembly tool (3)

 Valve assembly tools kit

*111589256100

 Depressor

*640589006100

6

Use magnetic pin (7) to remove valve keepers (6)

 Installation: Check valve keepers (6) for pittings.

 Installation: Ensure correct seating of the valve keepers (6).

 Magnetic pin

*210589004000

If there is a problem,



replace the valve keepers (6).

7

Remove upper valve spring retainer (4) and valve springs (5).

 The valves must not rest on the piston crown.

 Installation: Check top valve spring retainer (4) for pittings.

If there is a problem,



replace top valve spring retainer (4).

8

Use pliers (10) to remove valve stem seal (8).

AR05.30-S-3500-02SE

 Removal:
Use  pliers (10) to remove valve stem seal (8).
Otherwise, the valve stem seal (8), the valve stem and the valve will be damaged.

 Drift

*604589004300

 Pliers

*606589003700

9

Replace the remaining valve springs (5) and valve stem seals (8) in the same way, one after the other.

10

Install in the reverse order.