Can of worms: opened

[Jonah D'Avella]

So i know that everyone has an opinion on water pumps being good, bad, or just a bandaid for an existing problem, but I was wondering if it might me a good addition even in a good cooling system especially if I am driving in hot weather and sitting for a long time in intersections?

[Mark Gregush]

Yes, sure why not. I would run one if I need it. LOL like your title.
Did you get my last ok on the speedometer cable? Yes, I would still like it. When you get to it.

[speedytinc]

With a good cooling system, its absolutely unnecessary. By definition.(good cooling system) In fact adding a water pump to a good cooling system can CAUSE more overheating issues. Common issue is the pump moving too much water & not cooling the water necessitating a thermostat or other obstruction to slow the flow back down.
2) you open yourself up to a leaky pump shaft. More packing, more shaft resistance, more belt tension to turn,. Now you have too much tension on fan pulley bushings. Better fix with a ball bearing fan pulley.

You were right when you called it a band aid. A Montana buddy runs his racer around town without a fan.

[kelly mt]

I see a lot of speedsters run water pumps. What's the thinking on these higher HP T motors?

[Jerry VanOoteghem]

I see a lot of speedsters run water pumps. What's the thinking on these higher HP T motors?

Speedster guys like accessories and do-dads! My speedster has one. In fact, all my T's do! AHHH! The horror!!! Dad liked to use them. They don't bother me, so I don't bother them. Really, they're very little trouble. Do I need them? I have no idea. Maybe one day I'll take them off, but as long as they work & don't leak, I'll just leave them alone. I suggest the same mindset to Jonah. If you're not using one and everything works fine, then consider maybe leaving it alone.

Pump or no pump: enjoy your T's folks!

[mtntee20]

Jonah,

I do not remember if you posted about the engine coolant outlet neck. You can pull off the upper radiator hose and, with a flashlight, look down into the neck. You are looking for a thermostat. Some people use thermostats to get their engines to warm faster. IF you are having overheating problems, look for and remove any restrictions in the coolant flow path.

As for water pumps, you are right on the nose with the "can of worms". Many members HATE them. Many members Love them. It's your car, do what you think will be best for you and the way you drive. Many water pumps have a "paddle wheel" for an impeller. Very inefficient, but they do move water to some extent. The better water pumps have better-designed impellers and tighter clearances that impede natural convection (thermosiphon) when the engine is off. When it comes right down to it, there are two potential problems. First and most likely, bad radiator. Dirty, clogged, less than ideal tubes (round), bent fins, poor airflow. Second, high heat source, meaning timing too much retarded, running fuel-rich, poor seating valves, clogged or partially clogged head/block, poor exhaust flow. Some of these are easy to check and remedy, while some are going to be expensive.

There are members here that have spent the extra money and purchased a Berg's radiator. I have never heard any complaint (other than the expense) about a Berg radiator.

[Jonah D'Avella]

what does a thermostat look like?

[babychadwick]

There is a reason for so many water pumps being marketed during the time the T was being built. I assume at that time with competent radiator shops and relatively new radiators the lack of a "perfectly functioning" T cooling system was not the problem. Just saying

[TXGOAT2]

If you encounter a thermostat on a T, it will probably be one of the very common type used from the early 1950s thru the 70s. It will probably be located in the hose between the water outlet on the head and the inlet to the upper radiator tank, or else sandwiched between the cylinder head and the water outlet casting. It will look a little like a flying saucer, and exactly like a thermostat. In my opinion, a Model T without a water pump has no need of a thermostat and is better off without one unless you live at Point Barrow, and probably not then. If you run a water pump, I would recommend using a 180 F thermostat with a bypass modification. In a system with a water pump, the thermostat will allow the engine to reach and maintain operating temperature in colder weather and will act to prevent pushing too much water up into the upper radiator tank, assuming the radiator isn't plugged up. Restricting the pump's action at higher engine speeds at the water outlet will avoid pulling a suction on the lower radiator hose, which can cause steam pockets and promote leaks at the pump seal. A water pump seal can leak water out, and it can also leak air in at higher engine speeds, which is very detrimental. A proper thermostat installation can prevent this. It will also put a slight pressure on the engine block and head at higher speeds, which is all to the good, since it prevents steam bubbles. I'd say a water pump and thermostat are optional on a T or near stock T. I would NEVER run a flathead Ford V8 without thermostats and good water pumps.

[TXGOAT2]

Back in the day, people put well water, ditch water, and worse into Model T cooling systems. Cooling system problems were as common as tire problems, and many people did not have a good understanding of how the system worked. Many cars were routinely abused, and suffered from plugged radiators, radiators with pinched off tubes, careless operators, heavy carbon deposition, poor quality lubricating oil, overloading, and more. Where anti freeze was needed, it was usually alcohol-based, and had a lower boiling point than water. A water pump could keep the engine cooler, especially if the cooling system was compromised, and prevent the anti-freeze boiling off rapdily. Many Ts operated at higher elevations, and boilover could be a problem even with a good cooling system and a good driver. A proper water pump installation could prevent boilover under such conditions, particularly where alcohol-based anti freeze was used. We have better options today. A T with a good radiator and no water pump, fan, or thermostat is capable of averaging over 50 MPH for 500 miles in summer without overheating.

[Norman Kling]

This is my first experience with a water pump, and also the last, because I removed it and have had no problems since. I live in the mountains in California and it can get quite hot here in the summer and also up 6% or steeper grades. It can also get cold in the winter and some snow in the higher mountains. My first T had a water pump when I bought it. It leaked and shaft was worn out. A member who has a lathe made a shaft out of bronze, not steel as the original one. On one of my first tours, we went to the mountains in February, We stopped for a break and I noticed other members standing in front of their radiators to get warm. My radiator was cold, so the car had not warmed up even though we had driven about 35 miles up hills.
Another experience was when the pulley slipped on the bronze shaft and the set screw cut a slot in it like a lathe. When the pump is not turning, the impeller does not turn, so if the belt comes off or the pulley doesn't turn, the thermosyphon stops. Anyway, when I got home I removed the water pump and installed an inlet to the side of the block. Have had no overheating or running too cold since.

Having said all that, I don't think you need a water pump, if your cooling system is clean and in good condition, and the car is properly tuned. however, if you do use one, be sure it is in good condition, and use a good thermostat. Also check your fluid level often because they can start to leak unexpectedly.
Norm

[Charlie B in N.J.]

My last T, a ‘23 Touring, had a water pump on it. Installed by the former owner who only took it out for the Memorial Day parade in town. Claimed it cured his overheating. I kept it on. Bad rad? Who knows. Ain’t broke don’t fix it.

[paddy1998]

I can only tell you about my experience. My T came to me with a water pump on it so I left it there. I overheated all the time. Well not ALL the time, but a lot.

When I had to pull the head for other reasons I cleaned a truckload of crap out of it. Then I cleaned a truckload of crap out of the block. Then I had a specialty shop go through my radiator. Those things helped a bit too, but I was still overheating too often.

Out of options, I removed the water pump and haven't overheated since.

Yes the water pump functioned correctly; I still have it on a shelf and it spins freely with no leaks.

I have no specialized knowledge and some people might think I'm talking through my hat, but I honestly think the water pump was interfering with the thermosiphon cooling action.

Here's my logic: the water pump forces water into the lower jacket from the bottom of the radiator faster than the thermosiphon action would. This seemed like an improvement until I realized that the faster circulation meant that the coolant spent LESS time being cooled by the radiator.

Effectively, the water pump forces hotter water into the engine than the thermosiphon action does resulting in higher operating temperatures.

But what do I know? Like I said, I'm probably talking through my hat. Lay your hands on a water pump and find out for yourself. You can probably pick up a used one for cheap. It just has to spin freely and not leak.

Compare before and after and judge for yourself. Heck, it might work.

Another thing that helps a lot is NOT winding it up in low gear; shift into high gear a quickly as possible. More than anything else that kind of good driving practice helps keep my T from overheating.

[Steve Jelf]

what does a thermostat look like?

I don't get my panties in a bunch if folks want to use these things. It's their money. I'll spend mine on things I need.

[TRDxB2]

There are many things that come into play to keep a Model T running at its most efficient operating temperature. Most would say that is between 160°F and 180°F in order for the Model T thermosiphoning cooling system to circulate fluid through the system. A thermosiphoning system is intended to cause circulation without the need of a "pump" (more on "pump" later). So how does the fluid flow?
I'm sure your familiar with the saying "heat rises and cold air falls" and that is basically how the Model T cooling system is design to operate.Think of the system as a loop shown in the picture below. The hot fluid being less dense than cold, rises to the top of the system and in a sense is pushing the cooler fluid down in into the radiator, likewise the falling cooler fluid is drawing the fluid down causing the circulation.

The function of a thermostat is act as a valve to block the flow of the fluid until its designed temperature is reached (lets say 160°F). There are two basic reasons to cause the coolant fluid to reach that temperature more quickly - one is for efficient operating temperature especially in cold weather, the other applies to modern car's hot water heating system (not applicable to a Model T).
PUMPs
Modern cars don't rely on Thermosiponing cooling. They have a pressurized system (and a thermostat). A Modern car's water pump uses centrifugal force to send fluid through the system while it spins, causing fluid to be drawn from the center continuously. The inlet to the pump is located near the center so that fluid returning from the radiator hits the pump vanes. The pump vanes fling the fluid to the outside of the pump, where it can enter the engine. The fluid leaving the pump flows first through the engine block and cylinder head, then into the radiator and finally back to the pump.

Here's a look at the impeller of two Model T water pumps. Now what is in question is how these would enhance the flow of the coolant when it was already in movement from Thermosiponing? Also if there was a blockage in part of the radiator core would moving the coolant through the system faster make it any cooler or would it reach a point of equilibrium? Personally, I don't see Model T era water pumps capable of moving coolant any faster once operating temperature is reached and the Thermo action kicks in.

Once last point. The fan is only intended to pull air through the radiator while the car is at rest. Once the car gains speed the engine compartment is designed as a closed box to cause a low pressure system with the hood louvers pulling the air through the radiator core out of the compartment. Altering the compartment by removing the engine dust pans (splash pans) or hood defeats the design and less engine cooling.

In summary
Model T radiators went through a series of designs to improve their cooling capacity. Dusty roads may have contributed to clogged fins on the cores. The use of local ground water containing unwelcomed minerals could have also ruined a few. Many owners swear by Berg radiators as the solution to heating issues. If you don't have a problem stick with what you have.

[Duey_C]

Some thoughts from the outlands...
There is truth in the statements of thermostats being used to limit water flow to cool. Ask a modern demolition-derby person and they might say that without the "restrictions" of a thermostat, the water moves far too fast to effectively cool the engine. Son included.
That note is for engines with excellent water pumps.
Myself, I say the original later fan was a silly attempt at a cooling fan. HORRORS! What? He's lost his mind! The blasphemy...
The truly worn out '24 Runabout (with a '19 engine) still has a silly water pump that barely moves water but I needed to graft a different maker's fan on the engine as I had no other. That little bugger has NEVER boiled-over in the harshest conditions. Levers up even.
The '18 with a '23 fresh upper engine is very ready to lose the pump as the engine is broken in and doesn't need the extra help of a pump now. It couldn't keep up at first runs by itself yet sports an original fan. Not a fan of the original fan.
Do what your T engine and rad wants/likes/needs.

[TXGOAT2]

I don't think how fast the water moves through the radiator is an issue. If it moves faster and spends less time in the radiator, it makes more trips through the radiator in any given time span. The type pumps used on Ts don't move a lot of water. Using a water pump with no thermostat is known to cause overcooling in cool weather. Another possible problem could be that a pump might cause hot water to "channel" down the middle of the radiator with the tubes to either side not getting their share of the water circulation. A thermostat would probably prevent that. I suspect that the balance of water pumps sold were used to preserve alcohol based antifreeze or to remedy a clogged system. A TT truck running in city traffic would probably benefit from a proper water pump and thermostat installation. I think AA truck radiators had an extra row of tubes and a slightly deeper shell than the cars. I don't know if TTs had a special radiator and shell. A T with a clean cooling system, 50-50 "green" antifreeze, and a fan will not overheat under any ordinary circumstances. A fan is only needed at very low speeds or sitting still, or plowing through mud or sand at low speeds. I'd want a fan on a parade car or a car driven in stop and go traffic. I'd think a fan would be a good idea on a TT truck, especially one running in hot weather country.

[TXGOAT2]

My car has a 4-blade fan on it. It definitely moves air through the radiator when sitting still at low idle. At all other times, it's just along for the ride. It does use some power at higher RPM. I suspect that the belt slips at higher road speeds. If so, the fan may actually be restricting air flow through the radiator at higher road speeds.

[TXGOAT2]

Another possible issue with water pumps on Ts: The pumps used back in the day used rope packing and plain bearings which required grease. It was not uncommon for some of the grease to be forced into the cooling system, where it combined with rust and dirt to form goo which could accumulate and restrict water flow.

[tmodeldriver]

Come on guys. Everybody knows that a T Model needs a water pump. I haul mine around in the tool box. Makes a dandy wheel chock when I park on an incline.

[John Codman]

As one who bit the bullet and bought a new Berg's radiator I have no water temperature issues. I suspect that water pumps were installed "in the day" because Model Ts were driven much more slowly on rural dirt roads - probably in low gear much of the time.

[TXGOAT2]

I'd bet you're right, John. Ruts, rocks, mud, steep hills, deep sand, hauling cargo and large families, running plain water or alcohol antifreeze... a lot of these cars no doubt pushed through deep mud, sand, etc at least several times a year, in hot weather or cold. I've seen a number of old pictures of T's mired to the running boards in seas of mud.

[TXGOAT2]

As I understand it, Ford considered the Model A cooling system to be a sort of hybrid thermosyphon/pump system. The thinking was supposedly that if the fan belt failed, the car could continue at reduced speed without overheating due to thermosyphon effect. The early V8s conformed to this thinking, too, with less than stellar results. The V8s higher specific power output and the design of the exhaust ports made very efficient water heaters out of them. Ford put the Model A water pump, which wasn't much of a pump, by the way, in the cylinder head. That's not a good practice. Ford stuck with it into the V8 era, but eventually joined the rest of the automotive world and put the water pump(s) on the return side of the system, which is much sounder engineering. Pumping cooled water into the engine is much better than trying to suck hot water out of it, and pressurized systems were a great leap forward. Hot water in a non-pressurized system which is near the boiling point, will actually boil below 212F when placed under suction by a water pump, and the pumps cannot deal with bubbly water. This would typically happen in warm weather at road speeds, and once the condition developed, it would feed on itself. It may be that adding a water pump to the return side of a full thermosyphon system isn't such a good idea. Thermosyphon systems are carefully designed to offer very low restriction to water flow. They work well when clean. 1930s John Deere tractors could plow all day using only the thermosyphon principle and a fan.

[Art M]

I thought about conducting a test to determine if a waterpump cools better on a hot day and using a good radiator. There would.be a lot of contributing variables to consider such as coolant type, waterpump brand or type, low head or high head, the list could go on. Just too much work for no purpose. It wouldn't convince anyone.

Conclusion: if you like them keep them on your cars, if you don't, just don't use them. Argue about something worthwhile.
Art Mirtes

[TRDxB2]

I thought about conducting a test to determine if a waterpump cools better on a hot day and using a good radiator. There would.be a lot of contributing variables to consider such as coolant type, waterpump brand or type, low head or high head, the list could go on. Just too much work for no purpose. It wouldn't convince anyone.

Conclusion: if you like them keep them on your cars, if you don't, just don't use them. Argue about something worthwhile.
Art Mirtes

I thought about doing it to with a problem radiator. But then reality hit - and like you if something was proven what difference would it make - no two T's are alike any more
If nothing else water pumps help dress up the left side of an engine.

[TXGOAT2]

A much more useful dress up device might be an external balance shaft driven by a cogged belt like a modern timing belt. It would need a very stout mounting bracket and it might end up looking a good deal like the accessory water pumps.

[Jonah D'Avella]

Balance shaft?

[Steve Jelf]

[bdtutton]

I just finished restoring my 1914 Model T and was planning to put a water pump on my Model T until I talked to a few people that told me they were more trouble than they were worth. I decided to go without a water pump and just use plain water in my system until I was sure it would not overheat or leak. During my first week of testing it was 90+ degrees every day and everyone wanted a ride so my touring car often had 4 people in it. I was surprised that even with plain water in the system the car did not show any signs of over heating under any conditions. I was impressed and am now convinced that a water pump is not needed on a Model T under the conditions I use my car. Since there are no problems and no leaks this weekend I am draining the water out of the system and putting in a 50/50 antifreeze mix. I should be good to go.

[TRDxB2]

My2C: I have a problem with referring to a vintage Model T water pump as a "pump". The expectation is that such a device would enhance the delivery of coolant in a problematic radiator by causing the coolant to move faster through the system and somehow even push it through. Consider the placement of these designs as shown in the diagram. Understand that the Model T cooling system is not pressurized, so the only way for coolant to get to the bottom of the tank is either by gravity or thermosiphoning.
In reading the following consider the coolant flow to start at a temperature below that needed to cause thermosiphoning and then ....
Position 1: Only has access to coolant that was already delivered to the head's water jacket by thermosiphoning. The position of a water pump at this location is too high for gravity to have much of an affect. It delivers coolant to the expansion tank in the upper portion of the radiator.
Position 3: Only has access to coolant that has been delivered to the water inlet position. This aligns to about the middle of the radiator so both thermosiphoning and gravity would cause coolant to be available and both of these forces would cause water to enter the water jacket in the head. Again it can't deliver more coolant than is already available to it. If the coolant in the radiator was low and below the input to the pump it couldn't cause more flow than what thermosiphoning was providing.
Position 2: Conceptually, placement of a "pump" at this position would be the most advantageous position but again it would only be able to contribute to the flow of the coolant that was available to it. Even if the coolant level was below the water inlet it might be able to push coolant into the water jacket
All of these "pump" locations are entirely dependent on the amount of coolant that is able to pass through the radiator core either by gravity and thermosiphoning. At most they might cause coolant to enter the expansion tank more quickly, but after that where back to gravity and thermosiphoning. Things would be different if it were a pressurized system

[TXGOAT2]

If you put a good pump on a Model T with a clogged radiator, water would stack up in the upper tank and overflow and once the water got hot at higher speeds the pump would be sucking on the plugged radiator and making steam bubbles. The combination of loading the upper tank and introducing steam bubbles into the system would do a good job of expelling the water, perhaps before the system reached 212F. Another issue with a period water pump is that a plugged radiator would make the punp packing quite likely to allow air into the system, which would aggravate the tendency to form steam bubbles and displace water out of the system. A water pump won't fix a fouled cooling system. Cleaning the system will fix it.

[TXGOAT2]

There used to be an elementary science class experiment wherein hot water was poured into a beaker, then the beaker was plugged with a rubber stopper and immersed in cold water. The water in the beaker would break into a boil due to the pressure drop. A Model T cooling system is actually a pressure system in that it has about 14 psi of atmospheric pressure acting on it. Anything that lowers the pressure on the system, or any part of it, will lower the boiling point of the water. Operation at high elevation and running a water pump with a dirty radiator are two situations that can lead to boiling due to reduced boiling point.