C200 aux belt tensioner probs

[Johncamera30d]

Hi folks this is my first post so pardon any mistakes, this is my second merc a c200 classic 2 litre it's a good car... But the tensioner squealed like a pig so I changed the belt, pulley, and tensioner as they were all shot. The parts went on great but after I select drive and hold the car on the brake the tensioner knocks really loud. But in neutral and park it's fine, I've swapped one tensioner for another and tried another belt but still no joy, the knocking continues so any help would be greatly appreciated.

 

[toolman1954]

Hi, Recently had a similar problem on my Sprinter, changed one pulley after another and in the end it was the Alternator pulley which has a clutch on it that was causing the knocking. I just put a new Alternator on as the old one had done 225000 miles and seemed an easier job than swapping pulleys.
-----------------And welcome to the forum.

 

[Johncamera30d]

Thanks toolman I think that's going to be my answer, I have passed on your advice to a fellow sufferer hope you don't mind, thanks again will let you know how it goes.

 

[BlackC55]

Hi folks this is my first post so pardon any mistakes, this is my second merc a c200 classic 2 litre it's a good car... But the tensioner squealed like a pig so I changed the belt, pulley, and tensioner as they were all shot. The parts went on great but after I select drive and hold the car on the brake the tensioner knocks really loud. But in neutral and park it's fine, I've swapped one tensioner for another and tried another belt but still no joy, the knocking continues so any help would be greatly appreciated.

Do you have a damper fitted too?

 

[Johncamera30d]

No there was no damper on it when I bought it and a search of parts catalogs doesn't show one although some models in the range did get them, I think I'm gonna have to check engine numbers if anyone has info that would be great.

 

[BlackC55]

The damper was a mod by mb for cars that didn't have one and suffered your type of fault. Get one from mb dealer.

 

[Johncamera30d]

Yay fixed it this afternoon, many many thanks to everyone for their help, once the damper fitted she was her old self straight away. A great feeling cheers to all for the advice.