W168 A140 Chain tensioner

[RufusT25]

Hi everyone, this forum is a great source of information, Thank you. Just as an Introduction I am Alex. We have a mercedes 2002 A140 long wheelbase that we have had for 5 years now, she has covered 70,000 miles. We have had the MAS done on it and now it seems that there is a timing chain issue, it started as a gentle whurring noise but over time this has developed into more of a knocking rattle. I took the poly V belt off and ran the engine and the noise has persisted. Does anyone know if it is possible to replace the tensioner without dropping the engine? has anyone done it? any help would be massively appreciated.

 

[Steve@Avantgarde]

I have had a couple of chains snap but not done any for timing chain tensioners. Sadly access is an issue for any kind of job like this and the engine will have to come out. I cant see how a chain tensioner would make a whurring noise then knock, normally chain tensioners just clatter and mainly when the engine is first started or is idling and the noise goes as the engine is revved.

Who has diagnosed this fault?