Model A overheating.

dynaflash_8

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1930 Ford Model A. Stock motor in good shape. So iv been fighting this overheating problem since i put on a new headgasket. The old one was leaking on #1, so i pulled the head, cleaned both gasket surfaces, covered it in copper-coat, and torqued it in 3 stages, 25-50-60 in the correct torque pattern. Car runs great. Put new plugs in it, and took the thermostat out because it was sticking closed. 10 min at 45 mph and its 190. Take it to 50 and it pukes. Has a brassworks 4 core rad, a pump in good shape, fan shroud, and a 6 blade fan. It pulls lots of air, but i cannot keep it from overheating. It never use to do this. Could they have given me a wrong headgasket? I flushed the block and rad yesterday, and they were clean. Put a thermostat back in, and no help. Belts not slipping, timing is spot on, so what could be causing this?
 
Was your head and block surface true and flat? How's your GAV adjustment? points,proper gap along with distributor/ rotor all four should be close to the same?
 
You could try doing a search here as this topic has been covered extensively in the past 3-4 months. Is it possible your w/pump is pushing too much water?? Some advocate grinding some off the impellars to "slow" the flow so the radiator can do it's job. Is it possible the new h/gasket is bad??
Paul in CT
 
It's best to lay the new gasket on the head to see how it fits and makes sure all coolant holes will be sealed, then lay it on the block to do the same check. Then if it looks good, go ahead and bolt the head down. I always use Copper-Coat on both sides of the head gasket and torque in several steps, then retorque as son as I run the engine for about 15 minutes. Could you have missed a crack in the head or block, or a bunch of junk in the rear of the block water jacket?

Any chance mice got in the open holes while the head or radiator was off?
 
Tom what gasket are you using on HC heads?

It's best to lay the new gasket on the head to see how it fits and makes sure all coolant holes will be sealed, then lay it on the block to do the same check. Then if it looks good, go ahead and bolt the head down. I always use Copper-Coat on both sides of the head gasket and torque in several steps, then retorque as son as I run the engine for about 15 minutes. Could you have missed a crack in the head or block, or a bunch of junk in the rear of the block water jacket?

Any chance mice got in the open holes while the head or radiator was off?
 
remove the fan shroud, and try / ride the car again . I take for granted the have the 2 blade fan on the pump. Grinding down the pump vanes could also help. But try the fan shroud removal first.
 
Was your head and block surface true and flat? How's your GAV adjustment? points,proper gap along with distributor/ rotor all four should be close to the same?

The motor has never been rebuilt so the surface on the head is your guess. Im guessing the GAV is the knob for fuel mixture, and i keep it about half to 3/4 out. points are set at .019, cap and rotor are good. Plugs are set to .035. Car is 12 volt.
 
1930 Ford Model A. Stock motor in good shape. So iv been fighting this overheating problem since i put on a new headgasket. The old one was leaking on #1, so i pulled the head, cleaned both gasket surfaces, covered it in copper-coat, and torqued it in 3 stages, 25-50-60 in the correct torque pattern. Car runs great. Put new plugs in it, and took the thermostat out because it was sticking closed. 10 min at 45 mph and its 190. Take it to 50 and it pukes. Has a brassworks 4 core rad, a pump in good shape, fan shroud, and a 6 blade fan. It pulls lots of air, but i cannot keep it from overheating. It never use to do this. Could they have given me a wrong headgasket? I flushed the block and rad yesterday, and they were clean. Put a thermostat back in, and no help. Belts not slipping, timing is spot on, so what could be causing this?

Your headgasket is allowing hot gases to pass into the water jacket. The more work you ask the engine to do, the more the hot gases from the explosion bypass the gasket and boil the coolant. You will not see water in the oil and if you remove the head you will not "see" a blown out part on the gasket. To test, put the car in high gear, lock the brakes and lug the engine while trying to move the car. Have someone look in the radiator while the engine is under load and the water will likely be perking. Solution..Have the head ground flat and install a new gasket correctly. That last step is not simple. Also, study Marco's timing proceedure and learn to time the engine correstly...."runs best half way down" doesn't square with Fords design.
Rainmaker Ron
 
Tom what gasket are you using on HC heads?

I have a stock head, but have used the copper gasket on a couple friend's cars with the high compression head. It's the same gasket Larry Brumfield recommends, Fel Pro 7013C, if I remember correctly.
 
Your headgasket is allowing hot gases to pass into the water jacket. The more work you ask the engine to do, the more the hot gases from the explosion bypass the gasket and boil the coolant. You will not see water in the oil and if you remove the head you will not "see" a blown out part on the gasket. To test, put the car in high gear, lock the brakes and lug the engine while trying to move the car. Have someone look in the radiator while the engine is under load and the water will likely be perking. Solution..Have the head ground flat and install a new gasket correctly. That last step is not simple. Also, study Marco's timing proceedure and learn to time the engine correstly...."runs best half way down" doesn't square with Fords design.
Rainmaker Ron

ok ill have the head surfaced and give it a try. That makes alot of sence.
 
Head was warped, and it should be back from the machine shop tomorrow. Ill let you all know how it goes!

wish me luck on solving this hot water problem
 
So i fixed the overheating problem with.....wait for it....

gasoline.


I had the motor out to fix my clutch, and i noticed there was a bit of greasy sludge built up on the overflow tube. Rinsed the radiator with gasoline a couple times, and each time it came out brown and disgusting. I guess that some of the grease from the water pump had gotton into the water, and made a fine film on the cooling tubes inside the radiator. Well the rust and dirt and other assorted gunk stuck to the grease, and clogged the radiator. After the gas rinse, it got some dawn dish-soap and lots of water.

Works like a charm now!
 
Did you fill the system with gasoline and run the engine, and then drain it, or did you just run gasoline down the radiator and out the lower outlet?
 
I had overheating problems years ago and finally I took the top tank off of the radiator. Many of the tubes were plugged from water pump grease and no amount of flushing would have cleaned that radiator. The top tank came off easily by partially filling the radiator with water to protect the core solder and a propane torch and an air compressor to blow away the melted solder. I made up a tool the same shape as the core tube using a brass welding rod and plenty of Gunk spray as a lubricant and with the tool, I pushed out the old grease into the lower tank. When I got through, the tank was very clean and the overheating problems were gone.

I have also had a cracked head that I did not notice and changed the head gasket twice only to have exhaust gases push out the coolant. Finally changed the cylinder head to end the loss of coolant problem. Ed
 
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