I am looking for help identifying the mystery bolt pictured. I found it in my plastic engine belly pan - 1991 Volvo 240.

https://www.pinterest.com/volvo240things/volvo-240/

A/C adjuster bolt.

I've lost mine before. I think it goes easily unnoticed because you can't really see it easily. Maybe you forgot to tighten that bolt during your last belt change?

Travis

yes, it's the back bolt on the rear a/c support bracket. good thing to catch it, it's easier to tighten when the bolt is square like this. notice the smooth panhead. you will need extensions on your ratchet with an universal joint and the easiest to tighten from underneath the car, but get the nut on from above. i believe it takes a 13 mm nut.

it will make your a/c compressor to get out of line if this bolt is loose or off.

an easy oversight for shops to forget to put on or to torque it properly.

regards,
byron golden
86 245
92 245
94 940

Never mind, you can keep it. I found a replacement.

Sometimes, when you lose things, they show up in the strangest places. And no, I'm not getting forgetful.
--
1980 245 Canadian B21A with SU carb, M46 trans, 3:31 dif, in Brampton, Ont.

Lock bolt for the alternator tensioner slide thingy.

Looks too short for the alternator. But I don't have a better guess. Power steering pulley adjuster? Hope the OP lets us know.
--
Art Benstein near Baltimore

Plug in your most re-volt-ing puns here...

There's one on the A/C compressor as well, isn't there? The bracket is a lot thinner, so the length would be correct for that application.

The square cross section above the threading tells me you should have found a nut as well.. The square acts as the counterhold when tightening a nut down.

I don't recall anything like that in the engine bay..perhaps the battery terminal? They usually have a square nut/bolt so you don't need two wrenches for loosening.

There should certainly be a prize for anyone who can identify that bolt from memory.

Thanks!

Thanks for everyone's help! Per your suggestions I looked carefully at the alternator and A/C mounts - it is the backside bolt for the A/C compressor mount. I just put it back in with a new nut.