MTFCA Forum

Over the last few months, I have been troubleshooting my radiator. When I was driving it beforehand, it started constantly boiling over after about 5 or 10 minutes of driving. Most of the tubes were filled up with rust and other junk. I took it to a radiator shop and he did the best he could but couldn't the clear the majority of the tubes. About a year ago I was given an aluminum radiator that was sitting in my shop. Since was made for a v8 bucket T, it needed quite a bit of modifications. A friend of mine has a TIG welder and over the last two weeks help me do the modifications needed. I installed it late last week and have been driving around quite a bit since. It is amazing how well it cools. The only places that exceed boiling point on the engine are the exhaust manifold and the interior of the inverted domes where the spark plugs go in. The output tube and the lower eingine is staying at about 80 degrees. I am nearly finished with it, except that I need to find an aluminum neck and welded on.

Good news. If you aim to make the car as "correct" as you can get it, the adapted radiator will let you enjoy driving it while you save up a pile of dough for a new Berg's.

Check the temp at the upper neck or top of the radiator. If you are getting a reading of only 80 at the bottom, you may be running too cool. If the top is around 180, that is a good thing. You may have to block off part of the air flow through the radiator to get that temp up with your super cooling radiator.
Good job with coming up with a solution, even if may only be temporary. But the old saying is, nothing like a temporary fix that is permanent.

Why would I want it to run hotter? The top is about 170 to 185

The boiling point is 220 degrees. 180 is about what the modern cars with thermostats are set at. When you fill the radiator to the top, the water will expand and some will run out the overflow. When it is about the right level it is half way up the top tank when cold. Boiling would cause steam to come out either around the cap or the overflow pipe. It would also gurgle if boiling. It is normal for a T to gurgle a few seconds if you have been pulling hard on a hot day and then turn off the engine. This should only last a few seconds. If it continues to steam and overflow through the overflow tube, then the car might be running too hot. Another thing which sometimes happens is when the engine idles in place for a long time, especially in such conditions as parades on a hot day, some T's will boil, but if driven at normal speed will not boil. This would be caused by the fan not pulling enough air through the radiator, such as a loose belt or running without a fan or belt. With a good radiator and clean block and a good fan it does not even boil in a parade.
Norm

Engines that run too cold foul the crankcase oil with water, soot, and unburned fuel. This leads to rust and sludge formation. They also use more fuel than necessary and will tend to collect more carbon in the combustion chambers. In cold weather, lubrication can be compromised due to thick oil . A cold running engine will tend to develop excess thermal stress around exhaust ports and valve seats when placed under sudden load. Aluminum pistons will not reach their proper running fit in a cold engine. Engines are designed to run in the 180-200 F range. If that was my car, I'd install a 180 F thermostat with a small bypass hole drilled in it in the upper radiator hose.

I'm not sure what a normal lower water pipe temperature ought to be, but I'd think around 140 to 150F in normal service on an 80 degree day would be about right. Around 200 at the water outlet is fine.

So, should I put one of those thermostat things in?

I would. It would need to be located at the water outlet. I would want to drill a small hole (1/8") in the plate to allow air and bubbles to escape and to be sure that hot water reached the sensing element on the thermostat. Some thermostats may have too small an opening to be suitible for a Model T. Suppliers sell thermostats for Ts. I have not boughjt one because my car runs about right as is. I don't know if it has a thermostat in it or not. It does have a fan and a Berg's flat tube radiator.

Jonah D'Avella wrote: ↑

Mon Nov 01, 2021 2:39 pm

So, should I put one of those thermostat things in?

I may have missed some thing. Water pump? Probably, likely, thats why thermostats are available.
Pump not needed here. Remove it. It was a patch for a bad radiator.
No pump? No. Winter front. maybe?

Jonah

you need to measure the top of the radiator (180F) and the bottom of the radiator (not the bottom of the engine). There is no coolant circulating in the engine down there, and it is far away from the source of heat. 80F is not a real indication of the cooling capacity of the radiator and I do not believe there is any way you're getting a 100 degree drop from top to bottom of the radiator.

Running in this weather with 180F water coming out of the water jacket is pretty much "perfect". A thermostat will get you to "perfect" quicker, but will not change the ultimate outlet temp appreciably