R107 Engine maintenance

[AAlb]

Can anyone tell me how to know when to chacnge the cambelts of an 500SL R107? I'm hearing a suspect noise at idle and I'm afraid it is resulting from the need to change the CB.

[lfedje]

I would suspect that they are not belts, but rather the timing chain. I just changed my chain at 116k just as a precautionary measure. Because mine is a 73 it has aluminum chain guides with a plastic cover so these didn't require replacing. Yours however will have plastic chain guides which should be replaced especially if your going in there to replace your chain. You may also find that your oilers which are made of plastic are possibly brittle and either broken or cracked. Mine were!

How many miles?

Loren

[bandit96]

Go to the "search forum" at the top right of the page and type "replace cam chain"
I saw the thread not too long ago that gave excellent step by step for checking cam chain tension and replacement. Thank God I didn't have to do mine, but the thread certainly simplified the process!
Bandit

[AAlb]

70 k.

[rowdie]

I think this is the link Bandit refers to.
MercedesShopWiki: M116/117 Timing Chain Replacement

[bandit96]

Originally Posted by rowdie

I think this is the link Bandit refers to.
MercedesShopWiki: M116/117 Timing Chain Replacement

Yep, That's the one!!
You da man!!

[Werner W]

Being I had no service history and suspected no such work was done on my 500Sl, like Loren I just had my chain replaced as a precaution, at 100K. I also had the three chain guides, chain tensioner, valve stem seals and cam oiler kits replaced while they were in there. The engine runs smooth and very quiet now. Not cheap, $1,900.00, but now I drive it confidently where before I was always a little uneasy about not being sure if the chain was good or not. I too had a slight rattle sound a startup.

Werner