Howdy all, Something in my gut is telling me not do paint my new aluminum radiator black with rostoleum grill paint. That it it could inhibit it's effectiveness. Is my gut correct? Thanks Member: Rochester Street Rods - Est. 1970 http://www.rochesterstreetrods.org CrossMembers Car Club - Hebrews 12:2 http://www.crossmemberscc.com
Montanal is correct and your gut feeling is wrong. Darker surfaces radiate heat better; a radiator painted black will shed heat faster than a shiny aluminum one. Not that it will make much of a difference, but painting it black will not harm the heat transfer properties, it will enhance it. Besides, a black radiator looks far better in a hot rod than an aluminum one. I painted mine recently when I had it out for a repair, I like it far better black. Something just wrong with an aluminum radiator in a hot rod, IMO of course...
Good! Now to make sure this grill paint sticks... Thanks for the feedback Member: Rochester Street Rods - Est. 1970 http://www.rochesterstreetrods.org CrossMembers Car Club - Hebrews 12:2 http://www.crossmemberscc.com
This radiator was a birthday gift. It's identical to stock other than being three cores, a modern (70's) cap, and no metal tube to dump expansion on the floor. It has a tranny cooler, too. It was a gift From someone who knew I wouldn't spend the money on my self. Very nice unit. Painted black (lightly) it will disappear into my engine bay like every other 66 year old part Member: Rochester Street Rods - Est. 1970 http://www.rochesterstreetrods.org CrossMembers Car Club - Hebrews 12:2 http://www.crossmemberscc.com
Your one in a million then ;-) Member: Rochester Street Rods - Est. 1970 http://www.rochesterstreetrods.org CrossMembers Car Club - Hebrews 12:2 http://www.crossmemberscc.com
Hope your Grille paint isn't too shiny, shiny black paint doesn't radiate heat as well as flat or satin finish. JW
Had my avatar aluminum radiator powder coated satin black ($40.oo) , looks great and looks like it cost $900
If it was made with an oval top it would look better but aluminum or brass/copper satin to barbecue black always looks best to me.
Barbecue paint is great for this, tough and heat proof. A couple of thin coats and let it go at that. Too thick and it acts as insulation, but black paint helps the heat to disperse.
Not one post here claiming a black radiator dissipates heat 'better' cited the physics that support that contention. It MAY be true....I don't know......but is this a 'belief' or a 'fact'? I am not questioning whether it 'looks' better or not, only how does that make a difference in how it works. For many decades vehicle manufacturers painted radiators black, but so were generators, starter motors, distributors and air filters. I believe it's true that dark colored surfaces absorb heat from an external source at a greater rate than light colors, such as from sunlight, but it's not immediately obvious to me what that has to do with dissipating internal heat. Since a radiator is a liquid to air heat exchanger, and the air flow contact with the fins absorbs the heat, exactly how does color affect that process? Ray
All colors have a frequency, ranging from gloss white to flat black. That's how. Try painting two cans of the same size, one gloss white and the other matt black and fill both with boiling water and see which one cools faster. JW
Its true, it's explained by Kirchoff's law of thermal radiation: "For an arbitrary body emitting and absorbing thermal radiation in thermodynamic equilibrium, the emissivity is equal to the absorptivity." Check this out, some car guys and a scientist test the hypothesis:
This is great info guys thanks. This radiator the shop press where amazing gifts because I never would have spent the cash, but there they were on my birthday. I felt like a little kid again Member: Rochester Street Rods - Est. 1970 http://www.rochesterstreetrods.org CrossMembers Car Club - Hebrews 12:2 http://www.crossmemberscc.com
Also I've assumed all along the tank could be painted any color I want but the fins are the real concern. Sounds like if I don't go to thick (of course) that I can paint them too. Does anyone know a semi-gloss? My grill paint is either flat black or gloss black. I'll add I've used the flat back with a shellac clear and it looks totally vintage but of course that won't work on this. The flat is like a chalk board so that would not work and the shiny is too shiny Member: Rochester Street Rods - Est. 1970 http://www.rochesterstreetrods.org CrossMembers Car Club - Hebrews 12:2 http://www.crossmemberscc.com
i think Smokey commented about painting stuff black, but i can't find it and don't have time to right now.
Buy a can of radiator paint at the auto parts store and hose it down. Don't get it on to thick. Forget about all the theories and crap radiators have been being painted since gawd knows when.
Bare aluminum radiators in old cars look really out of place...any black paint on it will make it look so much better. and my guess is you'd be hard pressed to measure a difference in performance, one way or another. But yeah, black is less reflective than bare metal, so it transfers more heat.
Jim, You will appreciate this if no one else does. I walked into the shop of an older friend when I was a kid and he was spray bombing an aluminum intake. I thought it was odd and took a closer look. There lay an offy 2x4 that looked like it had been adjusted with a ball peen more then once. I asked what was up and the old fella just said this, "if you aint proud of it paint it." I suppose that applies to aluminum radiators, don't it.
Eastwood sells radiator paint in gloss and satin black. $13.00 12oz can. Never used it so I don't know if it's any good. Seems kind of pricy to me.
Unless you dip the radiator in the paint, you won't get paint deeper into the core than maybe 1/4". Most of the core remains unaffected.
That depends on your technic and how close you have the spray devise from the radiator core, 1/4 inch, you must be standing across the room. JW
Good info guys. I will be painting at least the tank Member: Rochester Street Rods - Est. 1970 http://www.rochesterstreetrods.org CrossMembers Car Club - Hebrews 12:2 http://www.crossmemberscc.com
And I sure am proud of it haha just don't like anything shiny ok my engine or in my engine bay Member: Rochester Street Rods - Est. 1970 http://www.rochesterstreetrods.org CrossMembers Car Club - Hebrews 12:2 http://www.crossmemberscc.com
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