Overheating resolved (simple)

TheFargoA

Junior Member
Good evening,
I had spent quite some time trying to figure out an overheating issue. My A will run fine, then it will slowly creep up in heat until it overheats. It has a new radiator and I recently rebuil the engine. I could go on and on. However, some theorize that putting a thermostat in the output hose slows the water in the radiator and thus allows it to cool. What the heck, for 4.00 I put that in there, and it's fixed. The A runs 190 all the time, no matter what (analogue heat gauge). Additionally, many say that the higher heat helps the A run more efficient, and heat is no hurt to the engine, as long as it's not boiling. I recommend trying this out; what is there to lose?! Good luck on your attempt. The FargoA.
 
Good evening,
I had spent quite some time trying to figure out an overheating issue. My A will run fine, then it will slowly creep up in heat until it overheats. It has a new radiator and I recently rebuil the engine. I could go on and on. However, some theorize that putting a thermostat in the output hose slows the water in the radiator and thus allows it to cool. What the heck, for 4.00 I put that in there, and it's fixed. The A runs 190 all the time, no matter what (analogue heat gauge). Additionally, many say that the higher heat helps the A run more efficient, and heat is no hurt to the engine, as long as it's not boiling. I recommend trying this out; what is there to lose?! Good luck on your attempt. The FargoA.

Is that old crock still out there??:eek:
It's plain wrong! If the water is slowed down through the radiator so it can cool more, it is also slowed down in the engine also so it heats up more. End result: Zero gain.
Happy you have resolved your overheating problem, now you can enjoy your A .
 
With a properly rebuilt engine and a new radiator you should be able to run your A stock without overheating. Tbird is right. You have a timing issue. When you get that right you can put yout t-stat on the shelf.
 
I could be totally incorrect; however, with:

1. A non-pressurized Model A radiator; and,

2. Water flowing downward through the radiator tubes by gravity;

3. With a thermodynamic cooling theory like that ......... appears like one could place three (3) thermostats in the upper hose and it would be possible to make ice.

On the other hand, I think what could have happened is that initially an abundance of water was pumped into the upper reservoir of your radiator whereby you were losing water in your overflow tube until the water level got low and the engine overheated; and now with a thermostat, (i.e., a restriction of flow), less water is pumped into the upper radiator reservoir and you are not losing water through the overflow tube.

But who knows ....... might be a new type of unheard of Radiator Vapor Lock with a Global Warming relationship.

But seriously, Mr. Bill Williamson's trick works; i.e., place a large headed nail in the overflow tube to restrict losing radiator water through the overflow tube.
 
Is that old crock still out there??:eek:
It's plain wrong! If the water is slowed down through the radiator so it can cool more, it is also slowed down in the engine also so it heats up more. End result: Zero gain.
Happy you have resolved your overheating problem, now you can enjoy your A .

The goal is to transfer heat from the engine to the radiator and then to the air. If the slower water can pick up more heat from the engine and that slower water can transfer more heat to the radiator, then you do have a gain. The gain is a cooler engine.
 
FargoA,

Obviously, there are some who don't subscribe to the slower water theory and that's OK. I support the use of thermostats: Running at 190* minimizes wear and oil dilution/contamination and improves efficiency (gas milage). Anything you can do to extend the life of your engine sounds good to me!
-and Bill's nail in the overflow tube works too.
Happy motoring!

R/ Roger.
 
Good evening,
I had spent quite some time trying to figure out an overheating issue. My A will run fine, then it will slowly creep up in heat until it overheats. It has a new radiator and I recently rebuil the engine. I could go on and on. However, some theorize that putting a thermostat in the output hose slows the water in the radiator and thus allows it to cool. What the heck, for 4.00 I put that in there, and it's fixed. The A runs 190 all the time, no matter what (analogue heat gauge). Additionally, many say that the higher heat helps the A run more efficient, and heat is no hurt to the engine, as long as it's not boiling. I recommend trying this out; what is there to lose?! Good luck on your attempt. The FargoA.

The purpose of the thermostat is to keep an engine at its ideal operating temperature of approximately 160 to 195 degrees. Cylinder wear is reduced when an engine operates between those temperatures. The Model A cooling system was not designed for a thermostat. Adding a thermostat is a design change. It changes the cooling fluid flow when closed and when open as the orifice is smaller than the hose. A thermostat will allow and engine to get from zero to 160 faster than without one so yes less wear when cold. The question is what operating temperature will your engine be at with versus without a thermostat? If it does cause your engine to run above 195 more often than without in hot weather then wouldn't you be causing more cylinder wear?
 
A thermostat is designed to control the temp with a properly operating cooling system. It will also help slow the extremely fast flow that happens in an A just like grinding the water pump fins as reccommended in the instructions incld with many water pumps.
 
I don't know but maybe someone can reply. I thought that a thermostat was always put in the hot side, upper hose, in this case. Jack
 
Past radiator overheating problem; just in case someone has this particular maybe different type of radiator overheating problem.

My radiator is original on my low mileage 1930 Town Sedan; and when I received it, I noticed:

1. The original upper interior radiator baffle to deflect rising, pumped coolant was about 95% deteriorated; and,

2. The top of the original radiator tube was very low and not near the top; and,

3. Someone had pinched the radiator overflow tube nearly shut tight to reduce coolant from escaping out of the overflow tube; however,

4. The top opening of the overflow tube was cut so low from the top that it was still leaking coolant over time on long trips with the engine was running constantly.

Rather than pinch the overflow tube tighter to where less coolant would flow, I opened the round tube and carefully reshaped it to allow it to drain coolant, and then slipped a tight fitting rubber hose over the end of the tube.

The upper end of the new rubber hose extends upwards to almost level with the top of the radiator neck whereby no coolant is lost.

Radiator and engine's excess water pump grease interior coating mixed with dirt & grime was successfully cleaned by allowing engine to run with warm water mixed with POR 15 Marine Clean.

Now, on a 100 degree day, the interior temperature gauge registers 170 degrees.

Also tested coolant temperature with a candy thermometer submerged in the coolant with engine running ...... same 170 degree reading.

Hope this can help someone some day.
 
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Just for safety. If you are running 190 in this cool part of the year, you are not going to be a happy camper this summer . The temps your car will be running will very well be around 205-210. as others have said look for other small problems. Have fun modelAtony tony white Lafayette, LA
 
yep and all we are trying to do is toss in some helpful dialogue in case things don't work out. Nothing like a little harmless dialogue, such as would happen if this were all done in person. There has been no criticism
 
I agree, but, we know how sensitive some folks are. Helpful dialogue isn't harmless to some. He just made a statement and a recommendation with no question. I try to keep quiet lately.
 
If you are running 190 in this cool part of the year, you are not going to be a happy camper this summer . The temps your car will be running will very well be around 205-210. as others have said look for other small problems. Have fun modelAtony tony white Lafayette, LA

How's that?? If his cooling system is in good condition a thermostat isn't going to make it run hotter. Above 180° the thermostat will be WFO.
 
yep and all we are trying to do is toss in some helpful dialogue in case things don't work out. Nothing like a little harmless dialogue, such as would happen if this were all done in person. There has been no criticism
You are totally correct, hope you and others keep up the great work! Wayne
 
The reason the restriction (thermostat) in the upper radiator hose works is it causes a slightly higher pressure in the pump. This pressure increases the vapor point of the coolant therefore keeping the water flowing. As the inlet of the pump in the lowest pressure point, this is normally where the coolant starts to vaporize, and the pump cannot pump vapor, only liquid water. This causes a cascading effect, and boiling over radiator. That is why the restriction in the upper radiator helps the cooling system. There are two other theories that are pure bunk. #1: slower water flow helps cool the water in the radiator better. Faster water flow causes more turbulence which carries and releases heat from the engine better. #2: The water pump pumps so much water that it fills the top tank and runs over. The water pump cannot manufacture water! It can ONLY pump water that comes into the inlet, therefore comes OUT of the radiator bottom.
 
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