[Cubcadet_107]

I'm trying to figure out if something's wrong with my H's cooling system or not. It has me stumped because I'm not sure if what I see in the radiator is normal or not. Tractor is a 1946 Farmall H. Water pump cooling system. The system itself seems to work flawlessly. The tractor runs so cool you can put your fingers just below an exhaust manifold port and hold it there without getting burned.

The thing perplexing me is what I see in the radiator with the tractor running (and just after shutoff). When off and cold, looking into the radiator, its normal green coolant. When I fire the tractor up, I can very obviously see coolant coming into the radiator from the pump. If I understand correctly coolant enters the radiator from the top and then flows down. I am unsure as to whether or not I'm supposed to be able to see the flow of coolant this well, nor am I sure its supposed to be such a strong flow. The coolant itself turns from transparent/translucent green to an opaque green, though I would expect this with the power of the flow into the radiator. Perhaps my waterpump was replaced/rebuilt in the recent past?

It gets more confusing on shutoff. After shutting it off, a thin layer of white foam settles at the top of the radiator. Again, this is probably due to the power of water flowing into the radiator. Is my water pump just really strong??

I've been looking for signs of a blown head gasket, but have come up with nothing. The oil hasn't turned white at all, and the coolant stays green. The cylinders don't ever fill with coolant either, and the exhaust never smells sweet. Nor do I get any smoke from the exhaust. The machine performs just fine, and the cooling system itself keeps the engine very adequately cool.

So at the end of it all, is this normal operation??? I have no idea what it is supposed to look like in the radiator. I can get a video of it if that would help. If I had to guess, the tractor just has an abnormally strong water pump, but I'm not sure.

Edit... I just had a thought.. IIRC these tractors have thermostats in them, and I know they can get stuck. Perhaps my thermostat has gotten stuck wide open, causing it to have full unrestricted flow through the radiator?