Iam having my valves adjusted in the next couple weeks. Should I insist a check on the chain since this 82 240D has only 117K on it? Thanks guys!

Sure, have the timing chain, cam timing and tensioner checked. Once the valve cover is off for the valve adjustment it only takes a few minutes to do these checks.

P E H

That was more or less my thinking, but the guy that's going to do the valves looked rather surprised when I asked him to check. He's very familiar with benz diesels and thought they hardly ever go whacky. Said he'd never seen a bad one on a diesel.

Van Helden.

Why don't you do the valve adjustment yourself? It isn't difficult and all you need are four feeler gauges:.003, .005, .013, and .015 inch. and 2 14 mm wrenches. Make sure you tighten the lock nut as tight as possible and recheck the clearance.The tensioner is OK if it keeps the chain tight and you can search here for how to check the timing.

Your mechanic is correct that these parts rarely go bad but the tensioner did go bad on my 300SD between 200K and 225K miles. I am sure glad I checked the tensioner before I went on a west coast trip because if the timing chain jumps one tooth, you are screwed. The cam can break, the cam towers will break and the valves can get bent.

P E H