The Stovebolt Site Forums The Shop Area Engine Shop 261

I'm thinking I want to upgrade to a 261 for my truck and have read posts here telling what trucks they came in but my question is how do I positively ID a 261 cu. in. motor? I'd like to know what I'm doing before I go shopping.

Check out Patricks Antique Trucks web catalog. He gives the info you need to spot that 261. Inliners International also has good info on 261's. Good luck.

Here's jim Carter's info.

http://www.oldchevytrucks.com/blog/index.php/?p=754

Hey sleeve, Drew's link shows the captains bars on the block. That's what I would look for. Up here in Canada, the 261 came in Pontiacs from 1954 - 1962, I believe. That's where mine came out of.

I think the casting number on the block, not the head, would be useful in verifying a 261.

The Captain's bar on the block is not a definitive ID of a 261 engine (1954 truck 235s had the captain bars, too). Check Jim Carter's link, above.

The head and block casting codes and the engine serial number (ID) are the best ways to ID a 261.

Tim, I have worked on a lot of Chevs, and I have never seen Captains bars on any 54 235 engines.
I have seen that all 1953 Power Glide engines had them though.
I believe that in 53 the Captains bars were used at the factory to make a quick and easy distinguish between the splash 235, used in stick cars, from the full pressure engine, used with the Power Glide.
Then in 1954 the Captains bars were used on the 261 to make an quick and easy distinction between the 261 and the 235.

I'll check my 235 truck engines tomorrow, Dave.

I have been quoting for years Jim Carter's article about 54 engines having the bars (above the starter) but I have never confirmed it on my engines (I have four 1954 235s: three Thriftmasters and, I think, one Loadmaster).

"Watch for the “Captain’s Bars!” The 261 has two pairs of parallel raised 3/4 inch long bars cast in the block. This is not seen on a 235 except 1954. One pair is above the starter and the second pair is at the top middle of the left side of the block very close to the head. See photos below. The one exception is the early 261 produced in 1954 to mid 1955. It has only one “Captain Bar” above the starter but keeps the pair on the left side."

Here is an example of a March 5 1953 235 with Captains Bars. LINK

My 1954 261 does not have any captains bars over the starter area
Josh

Hey Josh, Chev has definitely done some strange things over the years.
I have seen a number of 54 261 with the captains bars, and no 235s.
I wonder if you can give us the casting date above the starter and the serial number stamped next to the distributor. I'm wonder if you have a replacement engine.

No numbers on pad and here is a pic of the #s more pics
Josh

Very interesting, Josh. As you said, 261 block casting code and no bars.

Dave, That Picasa link did not work for me. "Sorry, that page was not found."

None of my four 1954 235 blocks have bars above/behind the starter.

Josh, are the 1/4" bolts for the pan in a straight line on both sides, or do they curve towards the center on the distributor side.

I have a 1953 235 powerglide engine. It does have the captains bars above the starter.

Kurt

The oil pan bolts are in line no bend in pan side it also used the longer oil pump
Josh

Josh, I can't explain your engine. I thought the Aug 17 4 might be 1964 instead of 54 and be a replacement engine. Replacement engines I have seen used the 1955-62 pan design, ie; curved bolt pattern.

Link not working for me either. Both of my 261's a '54 and a '58 have the bars in both locations.

Got a 53 Powerglide 235 on the stand in the shop, got both pairs of "Captians bars" on it.

Canadian Pontiac 261’s started in 1955 and came in a number of different shades of green. Later ones have the pin boss cast in them but it is not machined.To my knowledge American ones are only alpine green or yellow? Examples here.(scroll down)