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Radiator upgrade

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Thanks Steve for the input !! I know I am probably making this too complicated, but the experienced radiator shop that works mostly on older farm tractors and industrial equipment has asked the question to see if I want to have a brass/copper(??) core or go with an aluminum core. Do you know which one you have had installed??

Thanks,

John
 
bluegrass john said:
Thanks Steve for the input !! I know I am probably making this too complicated, but the experienced radiator shop that works mostly on older farm tractors and industrial equipment has asked the question to see if I want to have a brass/copper(??) core or go with an aluminum core. Do you know which one you have had installed??

Thanks,

John
Click to expand...

It is copper or brass, John. My shop didn't tell me I had an option, but copper does have better heat transfer characteristics than aluminum.
 
Hi John,

I recently upgraded my BJ8 radiator and looked at what was available at the time, including aluminum vs copper, recore vs new, and eventually decided on recoring but with slight modifications to improve cooling. Note that the original radiators were flat fin type cores, not louvered and from what I have seen of one or two originals they were four row, staggered tube units (others please help, as I'm not sure exactly what were the original cores, as these were shown to me by the fellow at the radiator shop who had experience with the british radiators and was confident they were the original cores, but they could have been late model cores too, upgraded from original cores). Also, I'm an engineer, Mechanical, so I may get a little technical, so I apologize if I get too involved.

I don't have experience with the Moss radiator, but it seems to be consistent with what you would expect with a 'modern' recore from a heat transfer perspective. It has a serpentine fin core, tubes spaced at 1/2 inch intervals from pictures that are available, and I called Moss for more details like number of rows, size of tubes, number of tubes, etc. but no one could help me with the details.

Aluminum pros:

1) Light weight, so its easier to install or remove but saving gas or added acceleration is pretty minor
2) Heat transfer? No, but from what I've gathered, since copper cores have a solder interface between the tubes and the fins which impedes heat flow, the performance of copper vs. aluminum is about equal with the edge to the copper core.
3) Stiffer, the aluminum core is much stiffer than the copper, but I'm not sure this is a benefit since the frame of the healey is so flexible, the radiator should be somewhat compliant so it isn't trying to keep the front of the car aligned all by itself. I believe the steel original radiator side pieces are designed with flexibility in mind so minor twisting or pulling doesn't fatigue the copper bits.

Aluminum cons:

1) Repairability, it is much more difficult to repair an aluminum core since removal of the tanks is cost prohibitive.
2) Maintenance, if you wish to have it rodded out to remove blockage or fouling, again, removing the tanks is difficult.
3) Vehicle value loss, retaining the originality of the vehicle is important for resale value, and IMHO the original core with the Coventry Radiator works badge on it is very classy.

Recore vs New - generally if your tanks are in good condition, recoreing is much cheaper, but beware of which core you choose when you have it redone. There are many options available which most will leave to the radiator technician who is doing the work. In general, if you select the four row, staggered tube, flat louvered fin core it will look almost identical to the original core but with the louvering, will provide a significant upgrade to the original. It should be 2 1/4 inch deep, which is the maximum the side panels will allow without modification. This core is available in the US, and if your shop cannot provide it, find another shop. I, on my first try, left it to the tech, and wound up with a 3 row, serpentine fin louvered core which was insufficient to cool the car. I wasn't paying attention, and was busy at work so went with what he recommended. I wound up redoing it with a 5 row, flat fin, louvered unit by modifying the side panels to accept the deeper, 2 7/8, core. It looks almost as a stock, original core, and the bottom tank didn't need modifying, and I'm quite happy with its performance. It will still be marginal, however, on a very hot day if stuck in traffic but I'm continuing to study that issue and hope to identify the base reasons when things are warmer here in Oregon.

Anyways, good luck with your selection. Whether you choose Aluminum, upgraded recore, or new, the cooling performance should be adequate if your car is in good condition and you have sufficient air flow through the radiator.
 
Hello Jerry, thank you for your input and perspective as a engineer. I recommend visiting the Wizard web site and view the specs. They also say that copper has better heat dissipation over aluminum. However, they describe in great detail the advantage is wizards actual unique design and construction in this particular aluminum radiator that gives it a advantage. I happen to have a all original never restored Healey I bought with 39,000 miles. My upper brass tank was weak and had some pin holes as well. For me, it made more sense to install a brand new aluminum wizard because the original replacement was $400 more! However, I kept my original unit and will pass it on to the next owner. I too am very fussy about keeping my Healey original, but adding new aluminum Wizard radiator, Texas cooler fan and getting rid of that gastly design of a oil filter and upgrading to the spin on adaptor where the best things I ever did... As I said, I defiantly will pass on the original item to the next proud owner for historical reasons.
 
Jerry,

Thanks for taking your time to discuss the product options in a comprehensive, understandable manner. I know just enough to be dangerous: Armed with the suggestions and input of those contributing I know enough to ask the correct questions and will and hopefully have the knowledge to determine if the answers are making sense.
Just a note............I too called Moss several months ago to gain some specific knowledge concerning their new unit but was not able to come up with any answers except those in print on their web site.

John
 
Drambuie,

The aluminum radiator on our 06 Dodge Dakota is a good case in point. It has two rows of 1 inch tubes, spaced 1/4 inch apart. This is a very dense spacing compared to what is available in aftermarket radiators for our cars. But that isn't the most interesting part. The tubes are .030 thick on the inside compared to the normal .060 or .080, which means the liquid flowing thru them is very thin, maximizing the exposure of the fluid molecules to the surface of the aluminum, minimizing the boundary layer as the fluid traverses its course through the tube. When I calculated the fluid flow through our radiators, it is definitely in what we call laminar flow range which means very little turbulence so the warmer molecules in the center of the flow tend to stay in the center and don't have the opportunity to get close to the boundary layer where the majority of the heat transfer is occurring. Obviously this trucks cooling system is much more optimized than our older Healey system, and we are only talking about the radiator. Another difference in the systems is the hot air infiltration at low/idle speeds, the whole front of the truck is sealed, no air from the engine compartment can turn around and contaminate what is coming in to the front of the radiator. The Healey is a sieve, open all over to warm air from the engine compartment. I did a short test with a new thermocouple on my healey warming up. Now given I had at the time some exhaust leakage at the manifold which could have contributed to the results so I plan on retesting. I placed the thermocouple at the center of the radiator right at the X section center and started the car from cold. Almost instantly the inlet air temperature increased to 30F above ambient and stayed there for the whole test. It was warmer even before the thermostat started to open, so my only conclusion is that warm air from the exhaust was somehow getting up forward of the radiator, whether from the leak or from the warm down pipes I will determine later, but that is a 30 degree penalty that is significant.

Ah, I stray from the point..... The Wizard site does make some good points to their designs, and lets face it all newer vehicles are now sporting aluminum radiators. I'm glad you've had good performance with yours. It would be nice to be able to compare different radiator options fairly, say on equal footing with testing. Did you read the testing on the Alpine Tiger systems with regard to the different upgraded radiators? IIRC they concluded they all seemed to perform pretty much equally, and the main thing is the air flow through the radiator at low speed or idle conditions regardless of an aluminum or upgraded copper radiator.
 
Hi Jerry, I will definitely.check out the Alpine tiger testing article. When I set out to upgrade my cooling system, I began to take note of temperature changes under various driving conditions during summer, fall and winter temperatures. What really motivated me was hearing so many Healey owners complaining about their cars overheating and their frustration.I was no exception! As it turns out, one of the most common mistakes among Healey owners is somewhere along the line people had replaced the proper sleeved thermostat with a modern off the shelf type. Also, some people had their timing way off that greatly contributed to the problem as well. for many people it was a combination of things including old clogged radiators, bad water pumps and so on. I decided to rebuild the whole cooing system and my goal was to achieve constant 180 degree temperatures in normal driving conditions during warm and hot summer days..80 to 90 degrees and hold that 180 degree operating temperature at your advantage stoplight. So, by adding the proper sleeved thermostat, correcting my timing to 15 degrees with a advanced timing light, installing a new modern radiator, adding a Texas cooling fan I definitely achieved my goal. However, when caught in a interstate traffic jam...none of these improvements will help you. I know from experience! The only thing left to do now is add a kenlow 12 inch auxiliary fan to the mix to complete the package. As I was telling John in my early post, I suppose if I removed the twin auxiliary fans from my Nissan Morano I am sure it would begin to overheat in a traffic jam as well! One thing I might add, with all these improvements minus the auxiliary fan.. My Healey actually runs way to cold in weather 45 degrees and lower at 137 to 140 degrees. As Steve points out going to a 180 degree sleeved thermostat makes a good all around choice. Also adding insulation under the carpets and trans tunnel is a nice cooling solution...for the driver! Lol.
 
Jerry Rude

Very good post Matey------:applause:
 
drambuie said:
... My Healey actually runs way to cold in weather 45 degrees and lower at 137 to 140 degrees. ...
Click to expand...

Both my BJ8 and BN2/100M run cold in cold weather, and it baffles me. Both have 180deg thermostats; the BJ8 has a 'contemporary' sleeved thermostat (Robertshaw, with the sleeve soldered on as sold by BCS, I believe) and the BN2 has a parts store Stant. Last time out--in cold but not freezing temps; 40-50deg--the BN2 never got much over 120 except when sitting idle for a few minutes--and the BJ8 ran under 130 most of the time. Both will hold 180 on a warm day or pulling a load, but get stuck in stop-and-go traffic and both will come up to 200 or more (no auxiliary fans). I can't understand why an engine that runs cold a lot of the time gets hot so easily (thermostats have been tested 'on the bench'). All temps degF; and both cars' safety gauges have been overhauled and, presumably, properly calibrated.

All I can figure is there is enough incidental airflow around the engine when driving on a cold day to keep the temps below the thermostat set point. Note that the BJ8 and BN2 probes are in different locations (head upstream of the thermostat for the BJ8 and radiator top tank for the BN2).
 
Bob_Spidell said:
Both my BJ8 and BN2/100M run cold in cold weather, and it baffles me. Both have 180deg thermostats; the BJ8 has a 'contemporary' sleeved thermostat (Robertshaw, with the sleeve soldered on as sold by BCS, I believe) and the BN2 has a parts store Stant. Last time out--in cold but not freezing temps; 40-50deg--the BN2 never got much over 120 except when sitting idle for a few minutes--and the BJ8 ran under 130 most of the time. Both will hold 180 on a warm day or pulling a load, but get stuck in stop-and-go traffic and both will come up to 200 or more (no auxiliary fans). I can't understand why an engine that runs cold a lot of the time gets hot so easily (thermostats have been tested 'on the bench'). All temps degF; and both cars' safety gauges have been overhauled and, presumably, properly calibrated.

All I can figure is there is enough incidental airflow around the engine when driving on a cold day to keep the temps below the thermostat set point. Note that the BJ8 and BN2 probes are in different locations (head upstream of the thermostat for the BJ8 and radiator top tank for the BN2).
Click to expand...

Wondering if the gauges are hinky. Have you checked adjacent to the thermostat with one of those HF laser thermometers? My car has the 180 sleeved Robertshaw and has recently run 160+ in weather in the 40s. My HF tool will closely match the temp gauge.
 
steveg said:
Wondering if the gauges are hinky. Have you checked adjacent to the thermostat with one of those HF laser thermometers? My car has the 180 sleeved Robertshaw and has recently run 160+ in weather in the 40s. My HF tool will closely match the temp gauge.
Click to expand...

Certainly possible, but both were recently rebuilt, one each by Mo-Ma and West Valley. Also, when it is warm and the engines are pulling a load the temps settle bang on 180 which is the set point for both thermostats. I might swing by HF and pick up one of the IR temp sensors.
 
Steve. I could not find the robertshaw 180 with a sleeve when I replaced the thermostat last year; I located the 160 unit from either Moss or BCS I cannot remember!!
Is there another source that I am not aware of..........I would prefer the 180. Any suggestions would be appreciated.

Thanks,

John
 
Well: On a cold day

There is enough cold airflow through the radiator and around the engine to keep the temps below the thermostat set point.
 
Keoke said:
Well: On a cold day

There is enough cold airflow through the radiator and around the engine to keep the temps below the thermostat set point.
Click to expand...

That's what I've always assumed. Would be more logical with an aluminum block; the Austin lump kinda reminds me of the old cast iron potbellied stoves.
 
Bob_Spidell said:
That's what I've always assumed. Would be more logical with an aluminum block;
the Austin lump kinda reminds me of the old cast iron potbellied stoves.
Click to expand...

Yeah:

But the old cast iron potbellied stoves also performed their function of keepin you warm HUH. :jester:
 
I bought my AC 180 sleeved thermostat from Kees Oudesluijs in Holland. From the appearance of the box it came in, it was NOS. Later, someone placed an order with him for a box full of them and I got a spare. I don't know if he still has any left, but I'll ask him and I'll let you know.
 
BJ8Healeys said:
I bought my AC 180 sleeved thermostat from Kees Oudesluijs in Holland. From the appearance of the box it came in, it was NOS. Later, someone placed an order with him for a box full of them and I got a spare. I don't know if he still has any left, but I'll ask him and I'll let you know.
Click to expand...

I got one from Kees a couple years ago, but I'm afraid to install it. From what I understand, these 'fail closed.'
 
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