Foamy Radiator

jrvariel48

Well-known member
So I take out the Coupe tonight to pick up the wifey. Some guys are checking out the car and tell me there's foam under it. Great!! I get it home and pull the radiator cap off and it's loaded with foam. I instantly run to the computer and punch up the Ford Barn and search my problem. Now I'm confused.
Here's my info:
This has not happened before, 1946 59 motor, pretty stock from what I can tell, Skip Haney pumps with about 500 miles on them, no t-stats, open system,50/50 mix green stuff, runs about 180 degrees in the hottest weather. I live in Jersey and drive the car all year long. It's kept in a heated garage.
Anyone?!
 
The normal cause of foam in the water is a leak that is allowing air to be injected into the water system. Only other thing I can think of is if someone was being cute and put something in the water to make it foam.
 
Try plain water it may be your 50/50 braking down .You may need the pressure valve of SH ,his pumps pump furious amounts of water .ted
 
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If it is a brown oily foam you have oil getting into the cooling system. If it is a bubbly coolant color it could be a compression leak.
 
Get rid of the anti-freeze and run water with rust inhibitor added. I have the same problem when I try to run with anti-freeze. Can't explain it, but it happens. Water=no problem.
 
I don't run the car in the winter. However, I do put anti-freeze in during the winter just for protection if I would lose my heat. A couple of years ago, I did have to drive it on the highway in the winter and after about a 60 mile round trip, I had lost enough coolant to cause the engine to overheat. Foamed out the overflow. I do run thermostats but it is an original(39) open cooling system.
 
Do you think it's a wise choice to go with the high flow t-stats to match the SH pumps?

You have your coolant backing up in the top tank and losing at least a gallon of water out the over flow tube. You need to have a radiator that takes a 4 lb pressure cap but with your stock radiator you need Skips 3 lb on your over flow tube. Your over flow comes from the top of the tank. The pressure cap or 3 lb valve blocks off the over flow so the water can't back out of the tank keeping the radiator filled for months or even years. With the valve or pressure cap fill the radiator up into the filler neck the large diameter rubber hoses will take up the little expansion with temperatures under 210 degrees. Some anti freezes foam a little and even more when the coolant is low and the pumps churning air into the system. One poster mentioned he don't loose water with stats, reason is the stats he is using restrict the flow of coolant and the water is slowed down and does not back up in the tank. Same thinking as restrictor washers in the hoses or drilling holes or removing every other impeller on pumps that didn't provide much water to begin with. Bob Shewman provides the only stats I know of that allow enough coolant flow. Gadgiteer@aol.com Slowing the coolant flow is a waste of Skips high volume pumps which deliver almost twice the amount of coolant through the system. It takes more volume of water, more flow of water and more air through the radiator to properly cool these engines. Any one of these help and all three make for good cooling. The air part is hardest to over come at slower speeds and idle but above 20 MPH forced air from forward motion provides plenty of cooling. Stick with the anti freeze and don't worry about a little foam as long as there is no compression leak. G.M.
 
The stats may be a restriction to flow, but not enough to affect cooling in my engine. Granted Wisconsin is not as hot as down south, but we do get occasional high 90's to 100 deg temps. Hot weather has never kept me from driving my car. And I do not use Shewman's thermostats.
 
Do you think it's a wise choice to go with the high flow t-stats to match the SH pumps?

Skip does not recommend using thermostats with his pumps inasmuch as they are only high flow when there are no restrictions such as stats, not high pressure to push through stats. But thermostats are important for keeping the engine at a stable operating temperature and warming it up in the winter for the heater. So, it would be better, if you decide to use thermostats, to get the current high pressure pump replacements and use the Stant thermostats. That's what I've done with a 40-60 mix of Propylene Glycol anti-freeze (2 gal. with 3 gal distilled water) protects down to 5° and increases cooling since that antifreeze transfers heat better than the typical Ethylene Glycol. Plus a 4# radiator cap. Works great.

See Stant thermostats compared to Shewman's here: http://www.fordbarn.com/forum/showthread.php?t=143576
 
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Skip does not recommend using thermostats with his pumps inasmuch as they are only high flow when there are no restrictions such as stats, not high pressure to push through stats. But thermostats are important for keeping the engine at a stable operating temperature and warming it up in the winter for the heater. So, it would be better, if you decide to use thermostats, to get the current high pressure pump replacements and use the Stant thermostats. See them compared to Shewman's here: http://www.fordbarn.com/forum/showthread.php?t=143576

Skip does recommend ONLY the use of Bob Shewman's thermostats. This recommendation is sent with EVERY set of pumps Skip ships. He has done the flow tests on other stats and knows others restrict the flow. Do we rely on Henry's testing or Skip's?? G.M.
 
I have the Stant t-stats and Skips pressure valve, I just never installed them.
I guess that would be the next order of business!
Thank you
 
I have the Stant t-stats and Skips pressure valve, I just never installed them.
I guess that would be the next order of business!
Thank you

Don't need Skip's pressure valve on a 46, just a 4# pressure radiator cap. Does the same thing better.
 
Research the archives but I think I remember reading that Sierra brand antifreeze doesn't foam. I live in Southern California so I don't have a problem running with just rust protection. I tried the green stuff once and it foamed.

Charlie Stephens
 
I started running Sierra brand antifreeze in my Model A years ago to control foaming. It is propylene glycol, rather than ethylene (Prestone kind) glycol. Now, it is the only type I use in my old cars. Mix it according to the directions on the container, using demineralized or distilled water.
 
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