Losing Coolant

It is very obvious. The cap isn't leaking, if coolant is going out, it's through the overflow. My grandfather had that problem, he changed the cap and it hasn't leaked since
 
ryanheacox said:
My only other thought is that things could be plugged up and water is just getting pushed out the overflow? The engine was running great, plenty of power and very smooth yesterday. I figured it would run badly if it had to burn a gallon of antifreeze over 20 miles? I would very much appreciate your input.
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I would suggest that this is where your problem lies. Your water pump in good normal condition would be pumping your coolant at a faster rate than it can flow thru your radiator due to radiator being in poor condition. Your coolant will build up in the top tank and therefore out of you overflow. This condition can easily be confirmed by adding a rubber tube to your overflow tube and collect the overflow in a container as others have suggested. A nail placed in the overflow tube may help in reducing the flow by partially pressurising the top tank and forcing more coolant to pass thru the radiator, but this would only be a band aid solution. Your best long term solution is to take your radiator to a specialist shop that can rod it out if this is not a job that you can handle yourself. Or, if money is no object, replace radiator with a new one. Another thought is do you know anybody with a spare known good radiator that may loan it for a trial.
 
Ryan,

A. Losing one (1) gallon within (20) miles, with no water leaking from hoses, no water leaking from radiator cap, no water getting in oil thus making you oil look like milk, your assumption in No. 1 above appears "Right On".

"My only other thought is that things could be plugged up and water is just getting pushed out the overflow?"

B. Then in your added remark in no. 17:

"I noticed the moto-meter begin to spike in town, but before that I was driving between 45-50 MPH. It made it almost the entire trip running normally, only started heating way up in the last 3 miles."

C. This no. 17 remark indicates that "if" extending the overflow tube and "if" providing the nail does not keep coolant from escaping, more than likely a very typical vintage Model A radiator problem is occurring, i.e., your radiator tubes are possibly "partially" clogged and cannot drain coolant as fast as the water pump pumps coolant; hence, initially water exits out of the over flow until you barely have enough circulating coolant to cool your engine.

D. With your reported results of beginning to overheat after driving 45 mph for about 17 miles and losing close to a gallon indicates a strong possibility that your radiator tubes need cleaning so coolant falling down by gravity can keep up with the supply of coolant provided by your water pump.
 
After back flushing or rodding out the radiator, I'd also install a thermostat. This is better for the engine's quick warm up, and it slows the coolant flow some.
 
RUNNERBUN said:
I would suggest that this is where your problem lies. Your water pump in good normal condition would be pumping your coolant at a faster rate than it can flow thru your radiator due to radiator being in poor condition. Your coolant will build up in the top tank and therefore out of you overflow.
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You realize that this is physically impossible? No matter how strong your pump is, NO pump can put out more than it can pull into its suction side. However, vacuum (negative pressure) on the engine side will lower your boiling point and then you can get flash steam, which because of its rapid expansion, will blow coolant out of the system. Therefore making sure the radiator flows well raises the pressure in the engine, making for more efficient cooling. Watch this youtube video, Jackson does a very good job on it.https://m.youtube.com/watch?v=Ug01EW7UZGM
If link doesn't work go to youtube and search model a cooling system.
 
Hi Ryan,

FWIW: Not all Model A radiator problems are alike.

Again, appears you are correct in that your reported coolant loss in this case "is" one of your major problems here. Losing one (1) gallon after 17 miles & driving a little further while losing coolant can spell engine overheating disaster.

With an engine running, one does "not" even need a "water pump" on a cooling system to lose coolant out of a radiator overflow pipe. Model T's and tractors built as late as the 1940's had no water pumps. Coolant circulated very freely and quite rapidly without water pumps. Coolant even easily flows "upwards" to "fill" the tops of these radiators.

When coolant is "constantly" exiting the over flow tube while driving, in a few more miles, one will be up Crap Creek without a paddle because when his impeller is sitting in air, his Model A water pump will be transformed into a hot air windmill.

With no coolant circulation through your radiator your Model A cooling system resembles a WWII diesel emersion heater sitting in a garbage can of boiling water.

And Mr. Jackson did not cover this fact in his You Tube film.

Surprise us all & let us know what you find. LOL
 
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Whenever I have a leak I can not find, be it coolant, trans oil, or engine oil, I add some fluorescent dye to the system and after running it check various places with a infrared light. Even if it is coming out the overflow the dye will show on the bottom of the car and end of tube.
 
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Yes for sure the radiator is plugged . I had the same problem cured by a new rad .The pump is designed for a good rad and overwhelms the top tank with partly plugged rad (normally the centre third, too much waterpump grease) The system is not sealed so the overflow pipe pulls in air now and again so no vacuum in the system . The top tank then overflows but not continuously if you get my drift .

John in nice afternoon Suffolk County Rngland
 
Well, I'm glad the consensus is a plugged radiator. It's better than the alternatives. I will definitely report back with my findings on Friday. It would be really cool if I could find someone with a thermal camera. I'll also have to do some calling around to see if there's a shop in the area that can rod out a radiator.
 
Hi Ryan,

Prior to paying for rodding out, you may luck out and be able to clean the tubes with a few of the home remedies mentioned in the archives under Search.

Some radiators are clogged with water pump grease mixed with crud.

Others are clogged with minerals deposited from well water or treated tap water which is full of minerals after contacting earth.

POR 15 Marine Clean did the job for me on a dirty original radiator .... today, never exceed 180 degrees even in 100 degree weather.

Other may chime in with their successful Betty Crocker Recipes. LOL
 
Well, I dumped in a gallon of vinegar and ran the engine for 15 or so minutes last night. I'll take it out for a ride today, I think the roads are washed off by now. I'll see how that works out.

If anyone else has a suggestion on what to use as a cleaner I'd like to hear it.
 
If you think it might be grease, dirt, grime etc... in the radiator. Pull the radiator out, block off the inlet, outlet, overflow tube, put in 1 gallon of Simple Green concentrate and screw on the cap. Slosh it back and forth several times a day for a few days and then flush it out with water.
Get a cheap meat thermometer from the grocery store so you can check the coolant directly to see what the water temperature actually is.
 
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