MTFCA Forum

I am not looking to spark debate, but I will soon be replacing my radiator and am looking at the round tube high radiator. My current radiator is an old re-core with flat tubes and is beginning to show its age, not to mention it’s rusty and crusty inside.

I understand the basis of flat vs. round tubes, so I wish to hear the experiences from anyone that has ran a brand new round tube high radiator. I live in Northern Kentucky and summers are relatively mild with highs in the mid 90’s. My current thinking is that a new round tube would serve the machine better than the current old flat tube.
What do you say?

I have no dog in the round/flat tube fight, but I recommend having the old radiator re-cored.

I'm running an original round-tube in my '19. No troubles. Lots of Tours, both National, Regional and local. Never a problem (though for an original, that is a shockingly unusual circumstance). My point is, if mine still cools, you will most certainly do just fine with a new, original style round tube radiator. It will also look correct.

Nice looking car - Are you overheating or just looking to spend a lot of $$$ for grins?

$$$ fer grins

But in all seriousness, thank you kindly. This coupe has been my baby and she is almost, dare I say, “restored”. Or at least my take on it.

Eleven years ago when I bought my 26 Touring the first thing I bought a new Radiator. When it came I noticed it was a round tube. I have drove it in parades in Oklahoma in August with no problems and it still keeps the engine cool.

If your real concern is that it is “crusty” inside, then I would remove it and then seal the filler neck with a O ring to the cap. Now lay it down on the front and fill it with a gallon or two of cheap vinegar. Let it sit for a day or two. Then drain and flush with water. Now reinstall and fill with a antifreeze distilled water mix. Maybe fill it first with ordinary water just to be sure of no leaks.
Any this would be my approach.

I run a new Brassworks round tube radiator in my Duncan and Fraser wide body roadsters. I have never had problems with cooling. Think southern California temps.

Allan from down under.

A good original round tube radiator that still cools well is not common. I think your best bet is to have your original recored if it’s not the best at cooling. BUT you can always get a new Brassworks if you want to spend the money.
And as many others have learned the money and time trying to get a decent looking original to cool better you can use that money and get a new one or have your recored.

Are there any issues with recording. I have heard there are sometimes problems with recoring,

Round or flat, never had a problem with either. Most overheating is caused from engines built to tight or to high of compression, carburetor running to lean, timing to far retarded, dragging bands/brakes, etc. I think round if still available?? go for it.

Hank

If you have a showcar and want originality for judging purposes, choose the round tube radiator. If you want a more efficient radiator, choose the flat tube radiator. Because flat tubes have more surface area exposed to the wind passing through the tubes, they cool the water faster and have a more rapid heat exchange.

Twelve years ago, I bought a new Brassworks, high, flat tube radiator for my 1926 coupe for $600.00. Normally, I am a purist and prefer originality, but when given a choice between more efficiency and originality, I’ll choose more efficiency, especially where the engine is concerned in the year-round heat of Florida’s weather. Jim Patrick.

Steve, in his profile, he has a ‘25 coupe. Jim Patrick

...in his profile, he has a ‘25 coupe.

Yes, there's a picture of it. I would go with a Berg's if it's still available, or a recore if it's not.

Many thanks, the experience you all lend is priceless.

If you want your T to drive and not one to haul around and show how correct you have it I would get yours recored with a flat tube if you couldn’t get a Bergs. You would be like a lot of T owners who want to experience your car.

For several years in a row I drove a friend's 21 touring car in the Independence Day Parade in Brandon, FL. Weather so hot you could barely breathe. This car had an original round tube radiator and no water pump. It also had no motometer so the way I could tell when it was too hot was by leaving the radiator cap loose in the threads with no gasket. Perhaps three quarters of the way through the parade I would notice some little water bubbles at the edge of the cap or a tiny wisp of steam. At this point, during the many stops I would keep the engine throttled up two or three notches for some fan speed and she'd settle right down. From this I believe that a round tube radiator in good condition will do a great job. Plus they look cool. Bob

While I plan on driving my coupe, I think I will try out a new round tube. This could be a good experiment that may support or diminish the stigma round tubes carry. Not yet sure when I will get one, but I can update anyone interested in how it does.

A new round tube radiator with 50/50 mix of antifreeze with take care of the cars's needs, assuming the engine is in good condition and properly tuned up. A TT truck might be better off a with a flat tube radiator.

2 things; my crappy round tube on the 1925, on a 90+ degree day doing a parade I did have to add water. But heck, I have seen guys doing the same parade with better radiators adding water too. Next, how many people come on here and report their car runs too cool with clean block water passages and flat tube radiator, there have been a number of those reports.
If going for a re-core, it might come down to what you can get, flat or round.