M103 engine noise - Tensioner or Viscous CLutch

[del mar]

Good Morning,

Following a moment of madness / excitement I bought a 1993 300SL at auction - "sold as seen".....

Bodywork is good, some pealing lacquer but no rust. Interior is good bar drivers seat bolster and engine runs well. Car does appear to have been looked after in a past life.

Hard top is fitted, as of yet I cant even tell you if it has a soft top, will get a friend to help lift it off and then start having fun getting that to work ! I have read and watched most articles on rebuilding cylinders, but I hate tracing electrical problems.

Passed MOT first time, but the engine bay is noisy, it is a spinning/grinding noise. MOT mechanic looked at it and said Belt Tensioner, but could it be the Viscous Clutch on the cooling fan, which is always on ?

Thanks

Del

 

[carat 3.6]

Take the belt off and check the pulleys for play.

 

[jaymanek]

Could be water pump too.. any of the pulleys really..

 

[jonnyboy]

Agreed. Water pump a good candidate.
Back off the big bolt through the centre of the tensioner, loosen the tensioner adjuster and pop the belt off. Then check each pulley by hand.
There are belt diagrams on the 'net as you may well not remember the routing.

 

[del mar]

Thank you.

Will investigate !

Del

 

[balge]

If the viscous coupling is gone and driving the fan all the time - might be worth replacing it while you're at it? Mine is on it's way out but doesn't make any noise...