Replacement radiator-to pressurize or not

[Don S]

I need a new radiator,my present radiator is plugged and not repairable according to the rad shop. I have had a overheat problem for some time ,so this winter the rad will be replaced. I have talked with the Brassworks rad builders,as most of you know ,they have several to choose from. I am not into point shows,mainly touring,so what about the pressurized radiator? Any positives or negatives My timing is set properly,electronic ignition,Brumfield head,and light weight flywheel ,bearing shells.. Your input would be appreciated.

[Ron Lachniet]

I had my radiator re-cored last winter and since then have put on about 4 thousand miles and have not had to add water and have had no over heating issues even in 95+ temperatures. It cost half of what it would cost for a new radiator. Mine is not pressurized.

[hardtimes]

Originally Posted by Don S

I need a new radiator,my present radiator is plugged and not repairable according to the rad shop. I have had a overheat problem for some time ,so this winter the rad will be replaced. I have talked with the Brassworks rad builders,as most of you know ,they have several to choose from. I am not into point shows,mainly touring,so what about the pressurized radiator? Any positives or negatives My timing is set properly,electronic ignition,Brumfield head,and light weight flywheel ,bearing shells.. Your input would be appreciated.

Hey Don,
IF you have a rust free block, or reasonably so, you should not have concerns about pressurizing a Model A/B radiator. IMO, such pressure may show up as a head gasket seep/weep situation, at some point, where it normally wouldn't have otherwise. Of course, if you have perfectly flat head/block mate surfaces, and copper coated head gasket and properly torqued head...you should have no worries either regarding a few pounds of pressure. Choices are good, eh

[Mitch//pa]

Originally Posted by hardtimes

Hey Don,
IF you have a rust free block, or reasonably so, you should not have concerns about pressurizing a Model A/B radiator. IMO, such pressure may show up as a head gasket seep/weep situation, at some point, where it normally wouldn't have otherwise. Of course, if you have perfectly flat head/block mate surfaces, and copper coated head gasket and properly torqued head...you should have no worries either regarding a few pounds of pressure. Choices are good, eh

very good info from Rick
they work fine unpressurized since the begining of time so i lean that way and also feel that a weep / leak has more of a chance to show up going pressurized.

[Benson]

1. Will the Model A water pump and radiator hold pressure of 5 or 10 or 15 lbs. ??

In 53 years and 55,000 miles on the Coupe I have never seen a reason to test them ... They work fine, cool well and last a long time with no pressure cap.

50-50 antifreeze with distilled water (to keep calcium deposits from plugging the radiator tubes).

2. Another thing to help cooling is to install a leakless water pump and eliminate all of that grease that gets pumped into the coolant every year!

[Brian in Wheeling]

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For any type of regular use age I can see no reason to pressurize the radiator. Just sayin. I have a fairly new Bergs radiator, which fit perfectly, and also a clean block.

Brian W.

[BILL WILLIAMSON]

I'm just using a coolant overflow tank, inside the shell. IF I wanted to pressurize it, I'd replace it with an EARLY Volvo coolant expansion tank, that is set up with a 4 1/2 Lb cap.
(I posted this idea, a LOOOONG time ago, & NOBODY replied DIDDLEDY SHIT!!!---I thought it was a TRICK IDEA!!)---NOW, I'm going to BED, with my DOG!
Bill W.

[Mike V. Florida]

No need for the extra cost of pressurized. Save your money for gas!

[MrTube]

My two modern cars run 20 PSI caps and turn the fans on high @ around 230F. 210-220F is normal for them and they burn extremely clean.

A known fact is a hot running engine burns cleaner and keeps fuel from condensing on the cylinder walls which results in longer life.

Does the "A" need it? Of course not but I would recommend at least running a thermostat and keeping your system clean.

Personally, I like a stock "A". I like to drive the "A" as it was built aside from a thermostat. But, if you're going to do modifications like a pressurized system where should you stop? Alternator, A/C, heater, new 200HP 1.6L turbo 4 cylinder + 6 speed manual?

[JohnLaVoy]

We have found that a pressurized system puts too much pressure on the original pumps. Even the ones sold as leakless will leak with the full pressure system. The Rupert leakless pump has been used on the two cars we used the Brassworks full pressure radiators and are holding the pressure just fine.

[Bob Bidonde]

It is not difficult to pressurize the cooling system later on, so you can opt to go with a non-pressurized radiator.

In the Model "A," water loss is a significant problem that leads to overheating. The concept of replenishing the coolant on a regular basis is not well accepted and not commonly practiced these days like it was when the Model "A" was in its era.

In my opinion, a water recovery system using an overflow tank is worth trying first.

[BILL WILLIAMSON]

The use of the Volvo Expansion Tank gives you an option of changing back to a regular overflow tank, or back to stock, with NO modifications & it uses ONLY a 4 1/2 Lb cap.
A big advantage is added water capacity, a top tank filled with 2/3 AIR, DOES NOT facilitate the cooling process. A KAZILLION air bubbles in the coolant is counter-productive, AIR BUBBLES are INSULATORS of heat transfer.
Bill W.

[Don S]

Thanks every one for your comments,much appreciated,even yours Bill. Glad to see you'r active again, the barn is a better place when you express your opinions. I need a radiator,could be the pressurized one may be unnessary. More research to do.
Thanks

[Synchro909]

I replaced a standard non pressurised radiator last year with a Brassworks you beaut, all the bells and whistles pressurised one. The old one was ever so slightly below being able to do the job. Nearly $1K later and now I have one that is NO BETTER.
IMHO, they don't live up to their claims.

[Don S]

Synchro909 Are you sure your radiator was/is the problem. Timing,carburation,waterpump,and crud in the water passages in the block,can cause overheating.Having the same problem after installing a new rad is suspicious to me

[Synchro909]

Originally Posted by Don S

Synchro909 Are you sure your radiator was/is the problem. Timing,carburation,waterpump,and crud in the water passages in the block,can cause overheating.Having the same problem after installing a new rad is suspicious to me

Don, The engine was a fresh rebuild with only a couple of thousand miles on it. The block was hot tanked as part of that process so it was clean inside. Water pump was a new leakless one, the carburettor was a freshly rebuilt downdraft and the ignition was electronic by FS. I have considered all of those things and eliminated them one by one.
The Rad is the only other thing in the system.

[BILL WILLIAMSON]

Synchro,
Are you running a thermostat?, They REALLY help in controlling the water flow.
Look at it this way:
The ENGINE is a water HEATER
The RADIATOR is a water COOLER
The THERMOSTAT is like a little MAN, in the hose, operating a VALVE & deciding HOW much FLOW & WHEN
Bill W.

[Synchro909]

Originally Posted by BILL WILLIAMSON

Synchro,
Are you running a thermostat?, They REALLY help in controlling the water flow.
Look at it this way:
The ENGINE is a water HEATER
The RADIATOR is a water COOLER
The THERMOSTAT is like a little MAN, in the hose, operating a VALVE & deciding HOW much FLOW & WHEN
Bill W.

Bill, Yup, I had a thermostat installed.

[BILL WILLIAMSON]

Also remember, a thermostat is not always either open or closed, it "HUNTS" to stabilize water flow, as needed.
Did you know that VEGETARIAN is an old INDIAN word, meaning POOR HUNTER?
Bill W.

[a-bone newby]

I also have a reccored rad and put my car in the july parade it was hot and idled for a hour and half and no heat problems I think re core is a c lot cheaper and if your not looking for 100 points recore