'53 leaking antifreeze

[57j2olds]

Good morning,

Yesterday I noticed antifreeze on my garage floor under the Cub. Looks like after I ran it antifreeze is coming out from under the radiator cap.

Is this normal or do I need a new cap? Can I overfill it?

After doing some research, it looks like the original factory cap was a "no pressure" cap. The one on there now is a standard automotive spring type.

Is this my issue?

If so, where can I get the correct one?

Thanks

[Slim140]

Check the overflow tube, it may be broken at the neck. Common problem.

[57j2olds]

Is this tractor supposed to have a pressurized system?

[Slim140]

It only builds pressure from the expansion of coolant getting hot. There is no water pump to pressurize it though.

As far as your leaking issue, be sure the overflow tube isn't broken at the neck. It could be as simple as there is too much coolant in your system. Most of the Cubs I've had would leak if filled above the base of the pipe you can see in the top of the radiator. It has to have room to expand. Your Cub didn't have a spring when new on the cap, it doesn't hurt anything having one though.

[tst]

should have a no pressure cap, if its overfull it will pump out the extra coolant, full is about 2" below the neck

[Gary Dotson]

If you use a pressure cap, it needs to be a low pressure cap. I consider 6lb. to be about all I want to put an old radiator through. One thing to look at, though, most automotive caps are designed to work with a 3/4" deep neck. Early cabs have / had a 1" deep neck, your pressure cap may have no effect / pressure if you have that combination. Your leak, however, is probably just an overfilled system, seeking it's desired operating level.

[57j2olds]

ok, thanks a lot...

[Matt Kirsch]

Proper cold full level is with the water just above the core of the radiator, to allow for expansion. If you shine a light in and look at an angle you can see the top of the core.

What often happens is people check the water level religiously, find it low, and top it off. Next time it's low again because the excess ran out the overflow tube when the tractor got warm, so they top it off again. After a few cycles of this they get worried that something is wrong. Nothing's wrong. It's just how these old systems work. There's no expansion tank for the water to run into when the tractor warms up.

[Waif]

If the overflow tube is not taking care of the excess , the cap is the next best place to have coolant leave.
IF all is well , working the tractor hard will leak the rest of the potential excess out. Then not do it anymore.

I don't have data on how much expansion occurs in a full Cub radiator , but a wild guess is a radiator filled like a modern vehicles radiator will blow off/expand about a 1/2 quart of fluid or more.

As mentioned, fill level just covers core. That leaves the upper radiator for expansion room.

[Glen]

Hi,
Below is a listing for a new non pressure radiator cap at TM Tractor. You can look at the pics.
This style was standard on the Cubs then.
They have listings for the 2 pressure caps also.

http://www.tmtractor.com/new/co/1642fp.htm