I doubt it. Radiator shops usually paint the br*** radiators black and have done so for years. I have an aluminum radiator in my model A with a pretty warmed over sbc in it and I painted the front only black. It has no problem cooling. I can't imagine it being any different if I also painted the rear black.
Emissivity of radiant heat at the wavelengths ***ociated with coolant temperatures is far more sensitive to surface texture than colour. Since the function of a radiator is to radiate, you want a surface that will radiate as much mid-long-wave infrared as easily as possible. That is the mattest finish you can get, in whatever colour. Black is good because the near total absence of reflection makes the core disappear visually, and probably accounts as much as near-IR colour misconceptions for the traditional use of black paint.
...@Ned Ludd, I knew you would put it into language that all of us simpletons would understand!!!......
...Some folks choose to use Hi-temp bar-b-que grill Black just to be sure it will hold up to the heat. I would just be sure to use a good quality spray paint so as to not have to do it again later. Consensus has long been that it has no discernable affect on functionality, unless of course, you put 15 coats on!
In the old "How to Hot Rod a Small Block Chevy" Bible from the 70's, there was a section that claimed that black paint absorbs heat to a cooler temperature from the heat source... i.e. It will absorb the heat out of the engine block into the atmosphere. As mentioned above, flat paint, having a more irregular surface, will absorb heat a little better than gloss paint. I asked an old school radiator shop owner about that & he claimed "That's why we paint radiators flat black". It makes sense to me so, with the mind-set of "every little thing helps", I've always painted my radiators flat black, be it br***/copper or aluminum. (Though much heavier, I believe br***/copper cools better than aluminum) I.M.O., black looks better than aluminum... so if it helps cool a little better: Win/Win.
when painting the fins, don't spray head on, spray from an angle that coats the fins as lightly and quickly as possible, this way you get the coverage without the heavy paint buildup, your goal should be to camouflage the core, not insulate it with paint. I just used hi-temp satin black and never had a problem. (8 years of reliable cooling so far)
The local shop I have dealt with for more than 40 years will repaint old radiators black after hot vat dip or installing a new core in a old tank. Harvey, uses a mixture of flat black enamel & kerosene, HRP
Not much more ugly than a shiny aluminum radiator in a cl***ic car. Pricy but good stuff. https://www.eastwood.com/ew-radiator-black-12oz-satin-finish.html
Painting it black will improve heat transfer, not inhibit it. There are plenty of sources on the net that explains this, here is just one: https://gcsephysicsninja.com/lesson...t surfaces are also,in white or light colours.
I used some leftover chalkboard spray paint on mine. Basically it is flat. Just misted it on to cover the aluminum
The only time ever had a problem was when O repainted my '65 Ford truck after being involved in a accident, to try to hid my poor body work I decided to paint flames on the truck and they turned out pretty good, but after everything dried and all the tape and paper was removed I needed to spray a clear coat, I used Amerflint clear and like a idiot I didn't cover the radiator since I wanted to clear coat the yellow grill and bumper. That truck ran hotter than a 4 balled tom cat! HRP
This is fairly obvious, but I will say it anyway. Make sure you don't spray a thick coat. Clogging the holes in the radiator with the paint will cause problems, no matter if it's black or ****** pink. Mist coat guys, mist coat.........
Wouldn't it be nice if they were painted black already. Like steel wheels. Then someone would want it polished.
If the radiator was polished, the air would slip through it easier and faster, and the cooling effect would be increased, no?
Naw, would be like having the coolant go through the system too fast and not cool, right? I mean the air coming through needs to be there longer to cool the radiator more. I say paint it green. Martians don’t discriminate.
Aluminum radiator in my 32, looked like poop till I sprayed it flat black with grill, never a problem. by wicarnut posted Aug 24, 2013 at 12:12 AM
Imageon being in the sun on a hot 90-degree day and putting on a winter coat. I never paint parts that release heat.
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