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Radiator Replacement

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Mickey Richaud

Mickey Richaud

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Went on a drive Saturday, and had a wonderful time. The TR3 performed perfectly, but is still running hot. I've decided to replace the radiator, but need some resources from anyone who's "been there, done that."

Don't care about the hole for the crank, as I'm more interested in the motor keeping its cool in traffic. Am also replacing the fan blade with a TR6 plastic fan, so originality gets trumped by driveability.

Any sources out there?

Mickey
 
Hi Mickey,

I don't have a source to suggest, but if I were putting in a replacement radiator, I'd seriously look at aluminum since it will transfer heat more efficiently than brass.

On the other hand, I would offer some other suggestions before encouraging you to totally replace the radiator.

Have you talked to any local radiator shops? They can often recore your existing radiator for a lot less than buying a new one, and it will be virtually as good as new.

They can rebuild without the crank hole, if you wish. That alone will increase the radiator's efficiency by 10 or 20%. Recoring is also an opportunity to straighten dents, as needed. Plus, during resoring the radiator is usually stripped of old paint, which might be several layers thick and reducing it's efficiency, and then repainted. (BTW, Eastwood Co. sells radiator paint that's designed to cover with a very thin coat, to help maximize heat exhange).

You didn't mention if there are any other things you have done to address the overheating problem...

Do you have the radiator shrouds in place? That's probably the single biggest concern.

There must be a thermostat installed, or the engine will very likely overheat. Is the thermostat a sleeved type, or is it modern type with the bypass hose partially obstructed?

Has the cooling system been flushed within the past year or so?

Have you renewed the coolant mixture lately, and/or added "Water Wetter"?

The plastic fan will likely help a lot. You might give that a try before making a final decision on buying a new radiator.

On a TR3 I'd also consider an electic pusher fan hidden in front of the radiator, as a possibility. If used with a thermoswitch, it could be set up to only come on when needed, such as sitting in traffic.

There's lots that can be done to help the car stay cool, without a total replacement of the radiator. Still, sometimes that's the only solution. Hope this helps.

Cheers!

Alan
 
I had my radiator boiled out last month. Still have a crank hole.

That and an elecric fan have really helped my cooling, even in traffic. But, Fresno's 100+ weather hasn't started yet.

Wetter water and an oil cooler are being held in reserve.
 
Should have given more info in the original post. This is a small mouth TR3, so the shrouds aren't an issue. The radiator was replaced with a rebuild during the restoration, but it has run hot ever since. There is a thermostat - one of the skirted types, and the engine block was completely boiled out when it was rebuilt. Hoses are all fine - no blockage anywhere. I've got an auxiliary electric fan, and it makes a very little difference. I can only assume an inefficient radiator, and as long as I'm going to replace it, I want to go for the most efficient one I can find.

Mickey
 
Mickey, I had a good radiator shop take my radiator apart for my TR6, salvaged the frame and replaced the three row with a four row, all brand-new stuff. And cheap. Think I paid $164.00. I have now zero overheating problems. I didn't bother to paint the fins. Like them the copper color they are. Corrosion has not been a problem.

Bill
 
Hi again,

Reading the additional info, looks like you've done quite a bit already trying to improve the cooling system.

You might try adding "Water Wetter", made by Redline. Most find it drops temps 10-15 degrees. There is a new product for similar purposes, claiming even greater temperature reductions, but I don't know if it works, nor do I recall the name.

Recoring without a crank hole would be help the existing radiator quite a bit. The other posts makes good suggestions, too, about increasing the capacity of the radiator, although there's not a lot of room for a big increase.

The 6 blade plastic fan will likely help a lot.

Some folks don't like auxiliary electric fans in the "puller" location, i.e. in front of the radiator. The concern is that it's blocking air flow to some degree. I'm not so sure about that. Once you have the plastic 6 blade fan installed, you might experiment removing the electric fan for a test run, just to compare.

Also, there are various size and air volume electric fans. I've got a 14" puller just recently installed on my TR4 that's rated pretty high, but also pulls enough amps that I'm converting the car to use an alternator. It will likely be noisier, too. I've seen as large as 16" fans on TR radiators.

If you do end up shopping for a radiator, I still recommend aluminum if possible. Most of the repro radiators are long neck style, so will fit your car. Either Victoria British or Moss had one, I think, but I'm not sure if it was aluminum.

Other key factors, do you drive in hot conditions alot? Does the car have engine modifications, headers, anything that could make it run hotter and keep underhood temps high? I've just replaced the mild steel headers on my TR4 with stainless, one major reason was to be able to wrap the headers to reduce heat in the engine compartment. Mild steel can be ceramic coated, but I believe wrapped stainless gives the biggest temperature drop.

I hope you find some solutions.

Alan
 
If you can get a local rad shop to re-core it, do that. But, a while back, I stopped in at Grffin Radiator when they had a shop in Anderson, SC. They can build a radiator for anything, but may need the old one for a pattern. The price back then wasn't too bad, and they can do it in aluminum or copper and brass. Griffin build radiators for many of the NASCAR teams.
 
Thanks, Bill - will contact Griffin for pricing.

Mickey
 
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