Timing Chain Tensioner - Modification

REF. No. 05/66

To: OUR MERCEDES-BENZ PASSENGER CAR DEALERS

DATE: MAY 1988

SUBJECT:
MODIFIED CHAIN TENSIONER
ENGINES 601, 602 AND 603

As of July 1987 production the out-side diameter of chain tensioner housing sealing surfaces (d1, d2) are enlarged by 2 mm each. Accordingly, the dimensions of the sealing ring (237) are changed to 27 x 32 mm (previously 25 x 30 mm).





This modification prevents the formation of burrs on the sealing ring (sectional view B) when tightening the chain tensioner. Possible malfunction of the chain due to burrs at the oil supply bore are thereby avoided.

In case of customer complaints about noisy chain drive or oil leakage at the chain tensioner, the sealing ring should be checked for formation of burrs. If necessary replace sealing ring.

The modified chain tensioner (with sealing ring 27 x 32 mm) can be installed in earlier production engines.

Tightening torques are 65 Nm for the chain tensioner in the cylinder head, and 40 for the closing plug.





Effective Serial Number





Parts Information

In case of warranty:

Time Allowance
Refer to latest time guide microfiche

Damage Code
Depending on technical nature of customer complaint, please select appropriate damage code:

05111 36 Timing chain, noisy

05131 04 Timing chain tensioner, leaking

16 Timing chain tensioner, binding

36 Timing chain tensioner, noisy

05132 04 Timing chain tensioner seal, leaking