Cooling System Design Flaw

Kevin in NJ makes some excellent points.

Keep in mind that the Model A cooling system was designed to work without a thermostat and that the "inefficient aspects" would help to get the temperature up fast.

Marc
 
Ford engineers had about 25 years experience designing the cooling system by the time the Model A was produced. For something so poorly designed it's funny how they never overheat by design and engines have been known to run forever.
 
Ford used a coolant pump near the top of the engine until 37 or 38 (cant remember). Then the pumps were placed low in the cooling system, since they push better than they pull. (positive displacement pumps pull well). My model A never overheats, even on hot days, up long hills, so in spite of the shortcomings in design, it works just fine.
 
This comment is for humor only.
"coolents were different"
Kevin, are you saying they have re-engineered water since the old days???

I wonder if anyone has tried Deuterium (H2O2/D2O) for coolant in a model A.
 
From "We Never Called Him Henry" by Harry Bennett
Who was Harry Bennett? No one was so close to Henry Ford as was Harry Bennett. Harry was with Mr. Ford 30 years as a trouble shooter and personal confidant.
Fred Rockleman was the Sales Manager for Ford Motor Company during the Model A Ford era.
Mr. Ford thought he could do almost anything well. After a few years, as sales slumped on the Model A Ford, Rockleman made that familiar mistake-he criticized the car. He said the radiators, were overheating. They were, too. Mr. Ford had to let him go, Mr. Ford did not want to make changes to the Model A Ford that Rockleman has suggested.
 
Bob Bidonde said:
I am amazed by the number of faulty pre-1949 coolant system designs because basic fluid mechanics dating back to 1738 were not understood.
That is, the maximum flow will always occur where the resistance to that flow is the least.
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One thing that is missing in the picture is the baffle that directs the flow to #3 cylinder. I have found that when boring a block, #3 usually has the most wear. IMO that is because it runs a little cooler because of the baffle and thus just a little smaller in diameter causing more wear. I always start boring with #3.
 
Nobody has yet mentioned the effect of the flow of extremely hot air in the exhaust manifold that directs ALL of it past cylinder #4. If there were an exhaust header that took away the hot air from each cylinder directly, it should alleviate the problem of higher temps in #3 & #4.
And, if there were larger water flow holes in the head gasket around the rear cylinders it would help to even out the water pressure points in the thermal-induced natural flow.
 
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Ford_Freddie said:
Does anybody know if water wetter would lower the temperature significantly to improve the cooling of cylinder 3 and 4?
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Save your money.
The rear two will be fine if the junk and rust is cleaned out, the radiator is good, and the pistons have the correct clearance.
 
Bob Bidonde said:
I have a suspicion that micro-boiling may be occurring in the head at Cylinder 4.
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No, micro-boiling is occurring on ALL cylinders and is in fact how the cooling system works. It was mentioned above, the cooling system is a thermosiphon system and the water pump is just an "assist". The pump is not a zero clearance pump and if you stop the pump the water would continue to circulate. (If you remove the pump the engine will run very close to the same temperature so long as air is moving through the radiator.)

Steam forms in the water jacket on the cylinder wall.
The steam bubble 'detaches' from the wall and almost immediately condenses back to water but in the process it brings with it the heat off the wall.
Hot water rises.
The water jacket in the block is designed to allow the hot water to rise and as it rises it will draw behind it water, cooler water, to take its place.
The actual location of the source of the cooler water is not critical so long as it is below the source of the heat. (placing the inlet anywhere between the front and rear of the engine, at the same vertical placement, will produce negligible change. )
 
Tom Wesenberg said:
Save your money.
The rear two will be fine if the junk and rust is cleaned out, the radiator is good, and the pistons have the correct clearance.
Click to expand...

Most factual comment/statement yet ...I can just hear Henry telling this very same words to ...whomever , i.e.- clean block, clean radiator and water filled system, equals no engine overheating problems period !
 
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Ford_Freddie said:
Does anybody know if water wetter would lower the temperature significantly to improve the cooling of cylinder 3 and 4?
Click to expand...
NO, BUT, by selling the stuff & trading his $$$$$$$'s for COLD, DOS EQUIS beer, the WATER WETTER GUY controls HIS TEMPERATURE, while watching the SUNSET on an island with 1 PALM TREE!
Bill W.
 
The "A" engine has plenty of problems.

We'll start off with it being a 200 cubic inch 40 horsepower engine.

By today's standards an engine this size should produce 400 horsepower (121HP per liter), not 40 and it should last 200,000 miles and weigh less.

But it's not. It's a cheaply engineered, easy and cheap to manufacture and easy to repair engine from 1929.

It has cotter pins in the connecting rod nuts and an unbalanced crank. We can criticize everything about it and there's plenty to go around.

But, it should be respected for what it is. An extremely simple and reliable engine that was cheap to buy and easy to repair. It's one of the few engines I love working on!



Even a Duesenberg from the time has serious flaws, they didn't know any better.
How is the cooling system on a Duesenberg straight 8? I'm not being sarcastic, I'm actually curious.


It's amazing the serious mistakes GE made on early refrigerators. Their very first model (1926-ish?) had copper plates connecting the interior to the exterior of the cabinet in the door opening. These plates should be thermally insulating, but copper is the complete opposite. It caused severe condensation and rotting issues. I believe they referred to these as "breaker strips" All later models used Textolite (Formica).

They learned and they improved as did Ford.
 
Tom Wesenberg said:
Save your money.
The rear two will be fine if the junk and rust is cleaned out, the radiator is good, and the pistons have the correct clearance.
Click to expand...

Agreed.

But...

I would not classify it as a waste of money.
I use Redline Water Wetter for the rust and corrosion protection when I'm running water in the summer. I know there are other ways but for $9 it quick and easy.
 
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