Farmall B cooling system - Pressurized or not

The B came with a non-pressure system. As CNKS said, inspecting the filler neck will verify whether it still takes an original cap.

Having a water pump and whether it is a pressure system are really separate questions. A water pump attachment was available for the U-2 power unit from very early on. It was a bolt on that would fit any of the C-113 engines.

The Farmall C's were all equiped with a pressure system, even though they didn't have a water pump. As Hugh said, the same pressure system was added to later Super A's. As far as I know, water pumps and pressure systems were used on all 123 engines. IH put a few big-bore engines in some C's for evaluation. I don't know if they had the water pump or not. 500 of these tractors were built. They were not built at the same time so they may not have even all been the same.

The block change during Super A production was the larger lower bore for the C-123 engines, as Hugh described. It didn't have anything to do with the cooling system. Engines with water pumps used a head gasket with smaller holes in the water passage that did alter the water flow.

We had this discussion some time ago, I knew my tractor had been presurized since new. Some folks claimed none of thermosyphon systems were presurized, and finally Sam in NS found the stats on the Super A and the exact serial number at time of change. There was a change in the block at serial number 310300, not sure what affect that had on coolant chamber.

Billy's B would have been non-presurized from the factory. It's unlikely anyone changed it as the presurized and non-presurized radiators are different. It may be that blocks before serial number 310300, can not be presurized. That rings a bell, if someone who knows for sure would care to comment.

Also, you can tell if the radiator is for a pressurized system by where the overflow pipe is located. If it is in the upper side of the filler neck it is pressurized, but if it is down in the radiator it is a non-pressurized radiator. Roger

Since the larger C-123 piston and sleeve kits will fit in the old C-113 block used in early SA, also A, B and C. Therefor the changes made in the block must have been for cooling purposes. When I say this I'm thinking more of water pump being reason than presurized versus non-presurized. That is not to say what you've done will not work fine.

Back to the block, and why IH did the thicker sleeves on Super A tractors. It was less expensive to manufacture sleeves than cast two separate blocks.

The main reason I said it was unlikely anyone would put a presurized rad on a B is there were only roughly 25,000 of those presurized rads made. You were quite lucky to find one, not a lot of Supers have been junked yet.

Bear in mind also the serial number I quoted last evening 336711 was a tractor serial number. By that time engine serial numbers would have been about 1600 higher than tractor serial numbers. Just for example, my Super A tractor serial number is 336977 and engine is 338597 a difference of 1620.