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Discussion Topic:
Coolant foam
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Dustbowl |
04-25-2011 @ 7:05 PM
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Member
Posts: 74
Joined: Feb 2011
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What causes the coolant (water/antifreeze) in my 36 Ford radiator to foam? My car runs cool (with Skip's pumps and his back pressure device on overflow) but when engine temp gets up to about 160F, a foam is forced out the overflow. Then when engine is cool, I find the coolant level is down around top of the core.
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MG |
04-25-2011 @ 7:33 PM
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Senior
Posts: 1261
Joined: Nov 2009
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Take your car to a shop where the coolant can be 'sniffed' for hydro-carbons - an indiaction of exhaust gases usually from a leaky head gasket.
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ford38v8 |
04-25-2011 @ 7:37 PM
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Senior
Posts: 2765
Joined: Oct 2009
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I agree. Too low a temperature to foam up. The only other cause I know of for foam is that you have too much antifreeze in your system, or the wrong kind of antifreeze. I don't use antifreeze myself, but I hear that they use Sierra in the frigid north.
Alan
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supereal |
04-25-2011 @ 8:11 PM
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Senior
Posts: 6819
Joined: Oct 2009
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Foaming was a constant problem with unpressurized cooling systems, going back to the Model A'a, when antifreeze was used. While Sierra brand antifreeze seems to foam less, a better solution is Skip Haney's valve that is attached to the overflow. It provides mild pressure, and contains the coolant in the system instead of "decorating" your windshield. Foaming was less of a problem when these cars were built. In freezing weather, the system was either drained, or an alcohol solution was used. When glycol antifreeze was introduced, foaming became a major nuisance. I suspect this led to the general adoption of pressurization. As your car is running cool, it is unlikely you have a bad head gasket ot other problem.
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TomO |
04-26-2011 @ 8:15 AM
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Senior
Posts: 7256
Joined: Oct 2009
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Dustbowl Check your radiator cap and the installation of the pressure valve from Skip. Your radiator cap may be failing to seal or the valve is installed incorrectly. When the valve is installed correctly, it will take more than 3 lbs of pressure to open it and allow anti-freeze to escape. If your system is developing more than 3 lbs of pressure at 160 degrees, you may have a compression leak into the cooling system. A good radiator shop can check for combustion by-products in the cooling system and the pressure build up in the system. They can also check out your radiator cap. You will have to find a shop that works on trucks, as the modern cars do not have the large filler opening that our flatheads have.
Tom
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cresty |
04-27-2011 @ 12:34 PM
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Member
Posts: 32
Joined: Oct 2009
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HOW DO YOU PERFOFM A --one cyclinder at a time,-- LEAK DOWN "TEST ona Flathead 8??? THANKS ALL--
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TomO |
04-27-2011 @ 2:07 PM
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Senior
Posts: 7256
Joined: Oct 2009
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A cylinder leakdown test is performed by applying air pressure to the cylinder when the piston is at TDC and measuring the amopunt of air that leaks past the rings and valves. A leakdown kit contains a gauge to measure the amount of air leaking and a method to supply the air to the cylinder. Harbor Freight sells an inexpensive one. It is not as accurate or as easy to use as the professional tools, but it will let you know if you have a serious problem.
Tom
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37RAGTOPMAN |
04-29-2011 @ 5:01 AM
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Senior
Posts: 1963
Joined: Oct 2009
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cresty all you need is a aircompresser, with the adjustable regulater. and a old spark plug, take the porcelean out of it, weld a one of you air tool fitting to it, now you can screw it in a cylinder.back off the regulater, put the engine on TDC on compression stroke, becarefull. you will have to lock the engine in place. putting in gear is a bad idea.because if the engine turns the car will move, I usually put a breaker bar on the crankshaft and lock it up against soemthing that will secure it in place,OR REMOVE the starter and use a pry bar,lock in the ring gear, you will need a buddy to help you with this, attach you air line to the fitting, now you can start letting the air in, a little at a time,you can start at lets say 25-35, and go up to 120 psi. which should be were the compression usually is at, have you radiator cap off and coolant to the top, take the oil filler cap also, as the air enters the cylinder, it will try escape, if you see bubbles coming up though the rad neck, you have a bad head gasket, or head leaking or a crack in the block, if you hear air in the oil breather,or dip stick tube you rings could be weak, if you hear air in the carb you have a bad intake valve, if you hear coming out of the exhaust pipe you have leaking exhaust valves, it is very easy and will tell you many things about the condition of you engine, if you hear nothing you are good to go,,, hope this helps 37 RAGTOPMAN
This message was edited by 37RAGTOPMAN on 4-29-11 @ 5:55 AM
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cresty |
04-29-2011 @ 9:34 AM
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Member
Posts: 32
Joined: Oct 2009
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THANKS,----RAGTOPMAN-----VERY STRAIGHT-FORWARD!!!
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ford38v8 |
04-29-2011 @ 7:37 PM
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Senior
Posts: 2765
Joined: Oct 2009
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Ragtopman, You say if I hear nothing, I'm good to go, but my wife yells at me to get my hearing aid fixed. I'm really confused now! Who am I supposed to believe?
Alan
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