1981 300SD timing chain new project?
 

Hey PeachParts,

My friend has a 1981 300SD. The car just turned 300k miles, but as he was driving home, the timing chain snapped on him and shattered the valve cover. I was thinking of picking it up as a new project. It is in pretty good condition inside and out despite this.

Is the motor repairable? If so, I'd like to pick it up as a project or help him to repair his. I feel like getting the timing correct would be a PITA. I most likely wouldnt keep the car since I have too many already, but it is a very nice car that deserves to be fixed.

Also along the lines of this, my motor going into my 240D is going to have 266k miles. Should I have a look at the timing chain before I run the motor?

Thanks guys,
-Josh

EDIT: dieselgiant just answered my question sort of, but I'd still like thoughts about it.

Generally speaking...no. the engine will have other damage besides the VC.

Bent Valves, broken Cam Shaft, bent twisted Rockers. Cracked head etc...
You won`t know if the Rods are bent or a cracked piston.

I would just R&R the engine with a good known one, and then deal with the broken one later.

With the blown engine, it is a $600 vehicle and a PNP candidate.

I had this happen at 65mph. every Valve hit a piston top.
At 331K miles, we just replaced the engine.

If this SD is in good condition other wise and you can get it cheap enough, go for it.



As to your 240D.
I think Roy, Whunter said he just replaces the chain after 150K miles, and especially when buying a new/used one. But with the mileage you mentioned. I would replace it and the plastic rails. The Sprokets will wear to a point, and they can add wear to your new chain. it is easy for the cam Sproket, the others a bit more work. It will be pricy to do it. If you do, use a German IWIS Chain.

Here is a good thread:
http://www.peachparts.com/shopforum/diesel-discussion/305365-9-degrees-chain-stretch.html

Have you checked the Timing Chain stretch? There is the 2mm lift check.
PeachPartsWiki: Measuring Timing Chain Stretch


Charlie

If the transmission has already been replaced or redone then you've got a potential engine swap on your hands - otherwise it could just be one big thing after another.

I might hold off on his car then. He is trying to sell it but its been sitting for the past few months. Luckily finding a spare OM617 isnt that difficult yet.

I had an 81 240D towed into the dealer about 14 years ago. The car got towed because the timing chain snapped. I knew someone who needed a new car. We bought the car. We did a head rebuild, timing chain, and all associated parts. The bottom end was fine. Was driven for another 8 or so years before it was sold for a W124 Diesel. I was just really lucky when I took it apart and it was ok. I'd recommend a new engine at this point because you probably won't get that lucky. The 617 is a dime a dozen in the yards. If the paint, suspension, interior and AC plus everything else is ok I would say buy it. W123 and W126s are difficult to find in ok shape at best and great shape is difficult.