how should I paint my radiator?

I got an aftermarket radiator, which works great excpt for the cheapo paint peeling off. what's the best way to repaint it?what kind of paint should I use? I'm think of heat transfer problems through the paint?

 

I would take all the old paint off with laquer thinner, prep with scotch brite and comet, then spray some self etching primer, then rattle can satin black.

The self etching primer is thin and sticks to aluminum very well, it wont peal.

You can get a Dupont etching primer in a rattle can, good stuff.

 

Unfortunately, cheapo paint is also the thinnest meaning little insulating value i.e. good heat transfer.
I use Krylon semi flat on the tanks, and the 99cent stuff on the core and only enough to color it
Be sure to clean the core before spraying! Sometime there is a lot of dust and such in there!

 

I had a Walker Radiator in my '23 T Bucket that I repainted. I was concerned about the heat transfer as well, but I ended up using Dupli-Color High Temp black and never had a problem with overheating. Make sure your radiator is clean of all oils/grease before you paint or the paint will never stick.

 

go to a radiator rebuider near you and get the paint,its a special asphalt based paint to help heat transfer and preserve the tanks and core.i dont thimk its readily available except to radiator shops who know where to get it.i brought my stripped radiator and the guy sprayed it for me for 15 bucks.i had to leave it there for a day to dry and it smells like road tar and was still gooey when i picked it up.

 

x2 on the Krlylon 1613

 

A couple layers of basic paint don't do much one way or the other for heat transfer and insulation. If it did, people would be using as insulation. Most old factory radiators were painted black and they didn't do it because they didn't know it held in heat. Touch a running temp. black painted radiator and see for yourself what kind of insulation it provides. Virtually none from my experience.

 

yeah, the worst "insulation" is the boundary layer of air, so high velocity airflow is needed to scrub it off. Similar to what goes on in coolant inside.

insulated glass in House windows is similar. You get about R1 for the air stuck on each surface of the glass, so 2 panes is R4. Keeping the airspace fairly tight (less than 1/2 inch) achieves best R rating as it prevents a "convective loop" from forming. Early windows would have big spaces (a few inches) thinking a big R number would result because of the low thermal conductivity of still air. If convection didn;t count, an empty 2X4 wall would be R 11, just like when it is full of fiberglass. The fins on heat exhangers without fans have to be 1/4 inch apart to avoid choking the natural convective airflow due to heat.