Hi-
The threaded rod which tensions the alternator belt broke on my 1968 220D, W115. I believe the part # is 1211552023. If need be, I suppose I can ask a friend to weld it back together, but I would prefer a more reliable solution like a replacement.

I don't know which other cars have the same part, but I do know that the later 240D W115 cars used an entirely different alternator mounting system.

You can see an image of the part on an earlier thread where I asked about how this might have happened:
Broken Alternator Tensioner: Did I do this?

If you have this part for sale, please PM me as soon as possible. I would like to get the car on the road soon. Thanks for your time.

Andrew

Did you ever find the adjuster rod? I may have what you need from another model. They used it on almost all of the cars back then.

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Cars:
1993 400E
1993 300TE Wagon
1985 300D Turbodiesel w/ 688,000 Miles On Original Eng/Trans
1979 300SD
1977 Euro 6.9
1967 230S IMA Universal Wagon
100 Or So Parts Cars

You Cannot Change your Future Without Disturbing Your Present

It Looks A Whole Lot More Like It Did Today Than It Did Yesterday?

Yes, thanks for checking. I was unable to get one here, so I scoured CL until I found someone in Spokane, WA who has parts cars available. Sometimes the interweb very much impresses me. I emailed him, he called me back, he went outside to grab the part, I "paypal"ed him $15, and two days later I had the part.

I plan to install this weekend. I am excited to have the car on the road again, because I have been hesitant to drive with a partially unsupported alternator.

I am having the same problem with the tensioner for the alternator. I borrowed a 1969 220D from a friend and the adjuster broke on me.

There seems to be an offset of about 3 cm between the front of the block and the back of the alternator. This makes me think the rod needs to be bent to create some of this offset. Is your tensioner straight or is there an offset in it?


I had it welded and it broke again the next day. I went back and had it welded again with a flat bar beside where it broke the first time so I'll see how this works out but I did want to know if I am going the wrong direction with my repair efforts.

wfward-
yes, it has a bend or offset. I will find a picture and put it up tonight. I was able to find a spare, but it wasn't easy. I will write more later when I get a chance.

This was the used tensioner that I bought, to show the offset. I haven't welded my broken one back together yet, but it will hopefully look like this when done. Mine broke along the angled, non threaded part, relatively near the through hole. Hopefully this photo is helpful.

When you screw it into the block, I believe the bolt should bottom out before it squeezes the through hole. In other words, the tensioner should not be tightly held at the block. What this means is that the tensioner is free to rotate which will eliminate any bending stress. Someone on my car used two lock washers to keep it from bottoming out, which meant that the tensioner was tightly squeezed. This adds bending stress, which might have been why mine broke. It is odd to have a part intentionally loose on a car, but I think it is designed to be able to rotate at the block. Good luck.

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I bet the dude in WA was a member here.
Glad you got your part!

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