w123 engine noise - timing chain?

[stuarth]

I ahve a 22 year old w123 diesel with 120km only. Sometimes when it starts and idles, there is a kind of tinkling sound from the engine a bit like someone lighlty tapping metal on metal. It is not tappets. TIming chian or something? Any foolproof test?
thanks

 

[landover]

Try the chain tensioner first.

 

[Mikesmerc]

My old 77 200D used to make a similar sound when cold, a sort of a crackling sound. I think it was a form of pinking much like what you would get in a petrol engine if the ignition timing was out.
Regards
Mike