Hello fellow members,
My 40 Super has a 263 motor from a 53 Special in it.I have been unable to correct an overheating problem and have narrowed it down to a possible crack between the valves.The question is : I have a perfect 248 head from the original 40 motor,Will it fit on the later 263 ? Has anyone done this? I could sure use help.
thanks,Ray

I find it hard to believe that someone can't help this new members question to give him some help .

I would be careful. According to the parts manual the '53 head is common to 51-53 for use with aluminum pistons.

Waycoolgreen
Hi, maybe I can help a little. Please respond to this thread and explain exactly whats happening that you say it's overheating. Does it get hot right a way? Is it OK around town,and not on the highway? Or when you get off the highway, it doesn't cool down? I need to know to help you.

Straight80

Yes, the 248 head will fit the 263. However!; The pre 1950, possiably mid 49 248 had the early small water pump and a different shape hole in the front of the head. The 263 and the last year of the 248 had a larger pump and different inlet/outlet ports. So, your 40 head will have the smaller different shape outlet port. It is possiable that if you use the thermostat housing along with the head it may connect up via the little hose between the top of the pump and the bottom of the thermostat housing, it's a by-pass thingy, a little monkeying around here wont hurt much. I've never tried to do this interchange because the early engines had cooling issues and in 1950 Buick finaly addressed them with the bigger pump and bigger ports and a change in the deck. The 263 is the best of Buicks str8's and I've run the waddin out of 'em, never found a cracked head. I'll bet you don't have one either. Most likely the block is full of crud. Buick addressed the cooling problem with the 263, but did'ent fix it. The back of the block has very low coolant velocity allowing junk to silt up progressivly to the rear. Pull out the freeze plugs, get in there with the garden hose and blast the heck outa it in there!! Even stick some various sized bottle brushes in there and brush around. That'll most likely fix it. alleycat

good info on this subject ! thanks alleycat

Wow, thanks for the help.I eventually sent the head out and it wasn't cracked but did have a couple of sticky valves.After installing it with a new steel head gasket(supplied in the FelPro kit) and adjusting the rockers ,it's seems better but still warm (195-205).While the head was off I syphoned off a lot of crud from the block.Now to give you a little summary.I replaced the original 248 with a 263 from a 53 Special.Had the rad flushed,replaced water pump,checked timing and flushed the coolant system.It would over heat after about 20 minutes.Decided to pull the head to see if escaping exhaust gas was heating coolant.Replaced it and it seems improved.Could the rad have picked up enough sediment since and not be operating right?Because the 263 is in a 40 Coupe could it not be getting enough air flow?
thanks for your advice, Ray

You have covered a lot, but there are couple of things I,m thinking about. the metal headgasket has given me some sealing problems. And I,m not sure about the bypass, the 248 had a valve that could stick closed and affect cooling, not sure about the 263.

Could the rad have picked up enough sediment since and not be operating right?

take an old pair of women's nylons and cut one leg off.

put that leg into the inlet side of the radiator with the toe at the bottom. keep the top of the leg up at the hose fixture and fold it over the outside of the fixture. when you hose clamp the hose over the fixture, this will secure the panty leg.

all trash will get caught in the toe of the nylons but it will be well down inside the radiator so you'll have the full length of the leg for water to pass through.

you can disconnect the rad hose and pull the nylon out every so often and check it for trash.

Hey guys, I didn't see any valve on the 263 that could close and cause flow problems.I'm pretty sure the head gasket's sealed well enough.I'm going to try that stocking trick as soon as I can snitched a pair from the wife.
Thanks,I'll let you know.Ray