Valve Spring: Service and Repair

Removing and Installing Valve Springs with Cylinder Head Installed:





1. Remove camshafts.
2. Remove spark plugs.
3. Remove fan shroud.
4. On Model 124, remove cover at compartment panel.
5. On Model 202, remove air cleaner top part.
6. On Model 140, remove fresh air blower housing.
7. Unbolt cable duct at component compartment panel.
8. Pull off center partition.
9. On all models, ff automatic transmission, unbolt dipstick guide tube at rear of cylinder head.
10. Install supporting bar (2) tool No. 111 589 01 59, or equivalent, with slide (7), bolt on with bolts of camshaft bearing caps.
11. Turn piston of cylinder to be machined with wrench socket to TDC. To do this, hold up timing chain so that it does not jam when turning.

CAUTION:
- If the crankshaft is rotated, it must be ensured that the starting position is restored so that the colored markings on the timing chain for setting the timing of the camshafts can be re-used.
- On no account rotate crankshaft back, otherwise the guide rail will be damaged by the timing chain.
- The relevant piston is in TDC position if the marking number on the vibration damper is aligned with the TDC pointer, as shown.

Marking Number Piston At TDC
TDC 1 and 6
120° 2 and 4
240° 3 and 5





12. Remove bucket tappet (3) of relevant cylinder.

CAUTION: On no account may a heavy bucket tappet (82 g) be installed together with the conical spring (yellow).

13. Screw in connection hose (4) of cylinder leak tester into spark plug hole.
14. Fix crankshaft in position to prevent rotating.
15. Pressurize compression chamber.
16. Attach lever pusher (9) tool No. 111 589 18 61 00 with thrust piece (5) tool No. 111 589 25 63 00, or equivalents.
17. Fit thrust piece (5) vertically at valve spring retainer (15).
18. Align thrust piece (5) and slide (7) relative to each other.
19. Fix slide (7) in position with bolt (8).
20. Compress valve springs (17) and (18).

CAUTION: Valves must not sit on the piston crown otherwise they will be bent.

21. Remove valve collets (14) with tweezers (6) or magnetic finger.
22. Remove valve spring retainer (15) with valve springs (17) and (18).
23. Remove valve stem seal (19).

NOTE: Valve stem seals (19) with bent metal casing must be replaced.

24. Remove bottom valve spring retainer (20) and check for pitting.

NOTE:
- Valve springs, top and bottom valve spring retainers with pitting must be replaced.
- The valve springs of the inlet and exhaust valves are identical.





- As of 11/93 conical valve springs version (B) have been installed in place of the cylindrical double valve springs (A).
- Pay attention to matching of bucket tappets