This explains everything. Well, almost. For the short time I was driving my 240D, I had trouble keeping the alternator properly tensioned. While installing new tie rods, I happened to look up at the alternator- an there is a "spare" hole! It's not spare, there is a bolt missing-and it appears to require a spacer to do any good. Apparently the car was sold to me this way, I never had a "3rd bolt" to tighten.
I don't know what the spacer looks like, but someone out there has one in a white plastic bucket for me, I'm sure. With the bolt.

Let me know?

Thanks

snapped_bolt

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'81 240D For now, a good place to borrow new parts
'80 300TD Probably will be put back into service!
'79 240D BACK IN SERVICE SINCE 09/16; limited use, oil leak. Guide pin r/sealed/replaced. Still a leak. Front crank seal....

Which one? Upper, lower, right, left? A junk yard is the best bet. The bolts changed over time so typing your VIN in the EPC and drilling to Engine > Electrical Equipment > Alternator will help you get part numbers if you decide to visit a dealer. Mercedes Classic Center can also ship it directly to you.

When I've needed to do this, I pull off an existing bolt and insert it in the missing space (if possible). This confirms thread pitch and helps estimate length. Then I take that bolt to an industrial supply store to buy a replacement. You can guesstimate spacer depth but I just get one from a dealer or Mercedes Classic Center - I don't know the alternator ones off hand but some of the spacers are HUGE and odd sized. It's not worth throwing off the belt alignment and wearing out the part even further with a bad guess.

Good luck.

Buy a new bolt and get one that is not worn away and loose. they arent very expensive.

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

Depends on the bolt - the upper right clamping bolt - which I doubt is missing - has a $45 list price. The others are $4.20 each. Should be a buck and change at a decent hardware store.

As alluded to in the original post....I had to look up to see it. This is the "lower" bolt.

I doubt that Mercedes made a half-dozen versions of this bolt and spacer. I have only been able to locate one spacer advertised online for the 1981 240D.

I am looking for original Cad-plated parts because they stay plated longer.

Thanks for the suggestions.

snapped_bolt

__________________
'81 240D For now, a good place to borrow new parts
'80 300TD Probably will be put back into service!
'79 240D BACK IN SERVICE SINCE 09/16; limited use, oil leak. Guide pin r/sealed/replaced. Still a leak. Front crank seal....