Painting An Aluminum Radiator

Is there any reason that I cannot paint an aluminum radiator?

 

To some small degree, I'd expect it to reduce heat transfer and hurt the maximum cooling capacity. But in the early days of autos the radiator cores were visible, and routinely painted.

Another point, however, is that aluminum is notoriously difficult to paint successfully, at least for long term.

 

Radiator is going in our '67 CJ, so it will be visible. I was thinking of just enough coverage so that I don't see the aluminum.

 

Just use a thin coat of flat black. We paint our condensers at work for corrosion protection and there is minimal impact on heat rejection.

 

Flat black is exactly what I was thinking.

 

I have an aluminum radiator on my 56 and it’s barely noticeable thru the grille. I honestly think it might be MORE noticeable if it was painted flat black.

 

I painted my Champion aluminum radiator with a very light coat of high-heat flat black stove paint.

It looks much more appropriate to me. The paint has held up and it's cooled well for over a year now.

 

In the 60's when we painted aluminum parts they had to be premiered with Zinc Chromate first or the paint would peel off. I don't know if that is still true or not, but when Teddy would paint aluminum dragster parts he always used zinc chromate primer first. Just a thought.

 

There are paints made specifically for radiators.

 

painting it black actually helps the cooling. A thin coat

 

That is the common theory, but I recall being told some other colors actually perform better, and that it is more to do with the surface texture than the color.