Inliners International Forums General Discussion Engines 235/261 rocker assembly

I've got a 848 head on a 261 block. The rocker assembly I have is off the 261. The rockers have been resurfaced and fit good on the shafts. In the book, 235's and 261's have different parts numbers for the rockers. Will the 261 rockers fit right or do I need to find a set of 235 rockers? I have one other set of rockers, off a 1953 splash oiler. They have different part numbers than the later model 235's too. Advice??
Thanks. joe

235 vs. 261 doesn't matter.

What matters in what year the cylinder block is because they changed the way oil gets to the top in 1958. 58-62 blocks use 58-62 arms. 53-57 blocks use 53-57 arms.

The difference in arms is the inside annular groove.
58-62 are offset, 53-57 are centered.
The size of the grooves are different also. If you try to use 53-57 arms on a 58-62 block, it will put too much oil upstairs.

I've got a 55 block and the rocker assembly that was on it originally. So by your message everything should be OK.

Why doesn't the head have anyhting to do with it? The 261 had the ball vavle rotators. Did the 848 heads use the rotators? Important question to me is if the installed height of the vavle stem is the same. If I understand you, the installed height is the same for all of them, but the oiling system is different. Is that correct. Thanks for the answer. joe

Yes, use your '55 rocker assembly then.

I've not seen any rotators used before. Nothing special in the shop manuals I've looked at either. My 261 didn't have any.

The cylinder heads are all the same from 53-62 except for temp sender size, chamber volume, valve guide installed height, and extra steam holes for the 261. There is nothing about any 53-62 head that would prevent you from swapping it with any other 53-62 head. The valve springs were a little stronger on the 261, and it may be possible the installed heights were different, but I would have to look into it further to be sure. I doubt it would really matter. I used the dual springs from Clifford and they are installed at a height different from stock anyway.
If in doubt, install at the specs for the year the head is. The date code is on the pass. side of the head.

Get a 59-62 shop manual and look at the engine section. It will show you very well what the changes were to the engine blocks.

The whole "drilled head bolt" issue comes from not understanding what the notes in the Master Parts Book said concerning its usage. It's really about the rockers, not the head itself. Use the right rockers with the right block, and it's a moot issue...

Head is marked J65 I've got a 1955 block and 1955 rockers. Everything should be OK. AND, I LEARNED SOMETHING!!
Thanks for the help. joe

J65 would be October 6, 1955, which would actually be a 1956 model year head. Check the date code on your block. It may actually end up being a 1956 as well.
Reason it matters is they changed the style of solid lifters from milk can to "regular" style, and the main bearings changed at some point as well.

Thanks for that tip as well. I knew the j65 meant Oct 6, 1955, but it didn't click in my head that that was after the year change. I've been thinking I had a 1955 block but maybe it's not. I had an issue with getting the right main bearings, dowel style. Didnt' find that until the rotating pieces were going together. Maybe I better check to see if I've got the right lifters as well. The ones in the engine when I got it were the older milk can style. I just opened the box of new ones and see they're the new style. Thanks again. joe

What does the stamped number next to the distributor say?

Cast in the block is C235 --- March 23, 1955
Stamped on the pad is O4I42I2 F255N I'm not sure what all that means.

Just talked with Patrick, he says that as long as I use the cam he sent me, with the newer style lifters and the push rods he sent that everything will work fine. It doesn't matter if the original engine had the milk can style lifters.