Radiator-cooling system problems?

I put a new radiator on my B yesterday and filled it with anti-freeze and let it run to circulate. Within 5 minutes anti-freeze was running out the overflow and was still doing it when I shut it off 15 minutes later. I did not overfill the radiator. What could be causing it to do this?

I wouldn't worry yet. It may just be finding it's own natural level.

Coolant will expand when it's heated (think of the overflow tank for the coolant in your car or truck). If you filled your motor cold up into the neck to just below the overflow, it would expand from there when you warmed it up, with no place to go except out the overflow. Go ahead and let it cool. It should settle down to about an inch below the bottom of the neck. If so, Id say you are fine. As long as you had it good and warm, it shouldn't overflow going forward other than a very little if you ever get it runninhg hotter than you have already.

That said, it did start overflowing fairly quickly given how slow these motors are to warm up and that makes me wonder if you have a sizable air pocket going in there somewhere. Air expands much more with heat than coolant will. Was/is the tractor on level ground when you filled it and were running it?

Uphill isn't really a problem as any bubble will make its way to the outlet at the front of the motor. If the tractor were pointed downhill, you could have a pretty significant bubble/air pocket at the rear of the head that could be heating quickly enough to force your coolant out.

You might try running the front of the tractor up onto a a couple of 2x planks which should raise it enough to move any bubble forward and out and see what that does to your coolant level. If you've been on level ground right along, I go back to the first point and suggest that it's just findin its natural level.

Hi
When draining and refilling or replacing the radiator or you have had the head off, air gets in the system. Refill radiator and run the engine till it heats up, without the radiator cap on. when it gets hot it will BURP, it will spit out some coolant and then settle down, you can then top it off , dont be suprised if it takes another gallon or so.
Bob S.

Thanks for the advice guys. It did take almost a gallon to refill. This site is great.

The early Farmalls had thermo sipion cooling systems, no water pumps. When they were new alcohol was used to keep from freezing, it worked well with the thermo sipion system. An antifreeze solution does not circulate as well. It still works and engines don`t overheat as long as the system does not have crud built up over the years.
When I first got my Farmal B I could smell antifreeze as I was running it, I thought it was leaking. It is just hot antifreeze vapor venting and it is not overheating or leaking.

Was the anti freeze pre mixed or did you add anti freeze and water without mixing?