Hey I want to paint my radiator black so that it looks new and good. But Im worried that the paint will cause some airflow restricion and thus cut my cooling. Can I do it or not?

 

I am not an expert in this but technically, when something is black, it radiates off heat better than any other color (look in physics book: 'black body radiation'). I'd be sure item is clean and paint not too thick, talk to several radiator shops about what they use.

 

Hey Wally,
How about polishing the copper underneath and seal with clear.
Looks sharp.
And for what its worth, Black absorbs the most heat. As in solar panels (for hot water)

bg

 

You should be able to find some paint made specifically for radiators at most any auto parts house.

 

bg suarez: It sure would look good but a radiator is kind of delicate to fool around with. I see at least two problems: cleaning and coating. Unless a special plastic, my guess is it would peel from the heat after not too long. I'd clean with hot clothes detergent and lots of rinse water, sun dry. Don't be tempted to brush those delicate folds of metal. They look like copper but I think they are a type of brass, which is part copper (+ zinc?).
When I do gas welding (lots of brazing), I clean with acids, and am VERY careful; only if you have no kids or pets around. Muriatic is for swim pools and is cheap (damn strong HCL hydrochloric acid, will pickle a nylon brush, use natural bristle). I use fingers, for a short time, as did Al Capone. Even diluted, this will probably eat up your radiator fins. Other acid is Phosphoric H2PO4 and will 'fix' rust. I got at Dairy Supply store for about $7-8 gal. One spatter of either will leave you reading with your fingertips. So kids: don't use these if you are under fifty, after that you are going downhill anyway. I'm 56 and know that I USED to run like a deer. But I can still work like a horse, with naps.

So bg,

 

You are correct that the incorrect paint will cause airflow/cooling problems. There is a specific radiator paint for painting them. It is very thin and needs to be applied in several thin coats.

Black paint is used because it aids cooling by radiating more heat off the fins increasing the efficiency of the radiator.

 

Thanks for the lesson guys! I just thought that the shiny brass tank looked good.