The Stovebolt Site Forums The Shop Area Engine Shop 235ci Engine Overhaul

I'm overhauling a 1955 235 engine and I have a couple of questions / concerns:

1- after removal and cleaning the block head I've found a couple of markings / stamped letter on the surface that contacts the block. They are "C" and "E". These are located in surface located near the # 6 cylinder valves. Also a raised letter "A28." What could they mean?
2- i've checked the block head for straightness using a 4 foot aluminum level. It appears to be straight. Should I still have the head refaced? How many times can you reface these cylinder heads?
3- The flywheel looks like it has some surface cracks. We have a 216ci engine and its flywheel is good. Can we use the 216's flywheel ring gear and use it on the 235's flywheel?

Texas - To partially answer your "1" question, I can't say on the "C" an "E" stampings, but to the best of my knowledge the "A28" is likely a casting date code. Check the top side of the head just inside the valve cover gasket rail by the head casting number as there should also be a casting date code there too. They should correspond to each other.

Others should be along to answer your head surface and flywheel questions.

Stovebolt heads can be resurfaced repeatedly- - - - -BUT- - - -the intake valve seats need to be recessed the same distance as the amount milled off the head surface. That little shroud area around the intake valve protects it from the flame front moving across the surface of the head as the spark plug fires, so it must not be compromised. The 1954-56 head can be machined to have the same combustion chamber volume as the later model "848" head by milling off .090" (3/32") as long as the intake valve seat is recessed by the same distance. Put .090" shims under the rocker arm shaft stands to preserve the correct valve train geometry, and run a lash cap on the exhaust valve stems.
Jerry

A28 is a casting code used by GM. A=January, 28 indicates the 28th day, so it was cast on January 28. The E and C could be identifiers of some inspector or shift leader. I doubt they indicate anything functional nor important. The three cracks you've shown there in my opinion would kill that flywheel. Any small cracks won't matter and generally will go away when you have it re-surfaced. Any crack large enough to put a straight pin or the end of a sewing needle into...please avoid using that one. As for the 216 flywheel, you can do that however I believe you will have to use the 216 bell housing and starter. Or, somebody here probably knows...maybe you could use the different starter gear ring that was used on the 235. The flywheel itself will bolt right up, however.

Usually a 3 character casting date like A28 would indicate January 2 of some year ending in 8. To get a 28th day of the month (or anything over the 9th day) you would have a 4 character casting date like A286 which would be January 28 of some year ending in 6.

Thanks y'all. Your responses helps me decide “continue or stop”. So far with your input I’ll keep moving on the overhaul.
As to the head it’s 3835913, D285. I’ve started lapping the valves/seats using Permatex Valve Grinding Compound (220, 180, 150,120. Plus I’ll finish with 600 grit. Shortly I’ll have it resurfaced by excellent engine shop (Villas Motor Works) here in College Station. So far valve stems are still in specs. Villas will also resurface the intake and exhaust manifolds.

The flywheel issue is defined and I’ll keep it for making something. When the time comes to R&R the 216 presently installed I’ll use its flywheel (pray it’s good) and its the bell housing (though the 235 housing is in good shape.)

A junk flywheel with a piece of steel pipe welded into the center makes an excellent base for a bench grinder- - - -one that can be located anywhere in the shop that's convenient for the job at hand. Tap the ring gear off if you don't want it scuffing up the floor as you move it around.
Jerry