The Stovebolt Site Forums The Shop Area Engine Shop GM Alternator on a 261

I hate it when I assume stuff.

I swapped a 261 into our '49 2 ton. I was told that it was a straight in swap for the 216 that came out..

I ordered an alternator bracket from American Classic Truck Parts and it does not fit. The 261 block has a 3 bolt pattern on the block, one of the bolt bosses is raised, making it necessary to shim under the bracket to make it fit. Even then, with it shimmed, the bracket holds the alternator too far to the front and the pullys do not align.

Any thoughts from you experts out there?

Do you need this 55-62 bracket;

and, is this the bracket you got?

Both of the above brackets are for high-pressure 235s. I do not know if a 216 bracket would work on 261 (maybe someone else knows).

Yep, you nailed it.
I'll call them and RMA.

I just used the generator bracket and made some spacers out of tubing on my 261. The front mount bosses differ from year to year on the block, as I'm sure you noticed. The one from the 235 of the same year is what you need.

I used the 55-62 bracket shown above but still had to elongate the holes end to end somewhat to get the pulleys to line up correctly on my 261.