I have a stock 1954 Cadillac which normally has a black radiator. I am going to change to a more efficient core but wondered if paint on a radiator causes it to lose cooling efficiency.
I have painted a few and never noticed a difference...im sure if you spray it in real thick between the fins it probably wont do it any justice make sure its clean or over time it will flake just do a dusting...enough for color
Was always told that black helps draw heat away from the core, similar to motorcycle cylinders that were painted for the same reason. Car radiators are painted black because it emits the most heat through radiation (highest emissivity). This improves the heat transfer out of the radiator when air isn't moving through the radiator. "black color = high emissivity/absorptivity" The reality is little of a car radiator's ability to cool comes from radiation, mostly from convection so in truth, the color doesn't matter
Might be able to find more info on this by using the "search" feature at the top of the page. Type in radiator paint. Seems like all the OEMs painted thiers. If it hurt cooling, they wouldn't have done it. I'm considering fogging a coat of radiator black on my aluminum one in the Chevy. Nothing thick or heavy, just enough to kill the silver color.
Black dissipates heat more quickly, that's why they are painted black. I have always lived by the philosophy that if it wasn't needed, Detroit wouldn't do it. Meaning if they can save a buck, they will.
I think they paint Brass & Copper radiators to keep down corrosion and black makes the most sense. MANY aluminum radiators in new cars are NOT painted, OE's saving money,
If you ask a "radiator" guy, he'll tell you not to use regular paint on the core, they have a special paint that keeps max efficiency......my 2c.... Aluminum doesn't need it, but I agree that seeing all that silver where it should be dark is not right for the look.......
mine is painted with high temp ceramic duplicolor paint. temp stays at 180 on the hottest summer days.
i think regular 'paint' in most examples is an insulator which would basically hold the heat in the radiator. this is obviously bad. radiator paint is 'special' or different or whatever and helps promote better heat dissapation. so, if you use radiator paint on a radiator i don't expect that you'd see a loss in cooling efficiency.
Father was a radiator mechanic for 25+ years and I have painted PLENTY of radiators for him. Believe me when I say there is nothing special about the paint used. Paint is usually thinned down with gas/whatever is handy to make it go further. Radiator shops are renowned for their "thriftiness" lol. They just look like shit when they're not painted lol. Generally like to turn green around leaking tubes/tanks.
For years people said that the wrong paint or too thick of paint would cause overheating. But Mattson's Radiator, who has been around for 50+ years and builds tons of Hot Rod and race car radiators, regularly Powder Coats radiators. I have used theirs done this way with no problems. So I'm not sure it isn't a bit of an old wives tail ........
CAD...a painted radiator make's it 3-5 degrees hoter, radiators have been painted black sence the 20s. and the reason their still painted black is because most of everything under the hood is black. that's it in a nutshell...POP.
My second "real" job was delivering radiators for a repair shop. As low man I got to paint a lot of radiators. They used a cheap flat black and thinned it with gasoline! Try that today! They thinned it to get the least amount of paint on the fins and tubes. They instructed me to prop the radiator up as it would be installed and paint with the gun pointing down from the top so as not to waste paint on the under side of the fins. They wanted just enough paint to make it look good for the customer.
EXACTLY! Look at it from the bottom and it looks as though it was never painted. Paint was so thin it was almost brown lol. p.s. holeshot is my ex radiator mechanic father
Aluminum corrodes rapidly,so its paint or corrosion.That is why airplanes are painted. My radiator started to show signs of corrosion inside of 6 mo's. Painted black Dupli color engine paint but only a frost coat spraying down on fins and tubes and light coat on tanks. Every thing rusts and corrodes in Fl, could hardly close my hand this morning.
I got tired of seeing the silver on my aluminum radiator on the T, so I fogged on some black paint. I had done a run up the hill, through the redwoods, and came home, parked it in the garage, and checked the temp gauge, and hit about a dozen places, including the radiator, with my infrared heat gun. Painted the radiator, repeated the same exact route, same ambient air temps, same speeds and as close to the same throttle position as I could, (except for having to nail it to get around a motor home on the way back to the garage from trip#2) and checked all the same places with the heat gun... Absolutely, no change... not one degree, no difference anywhere. Just my way of checking it out, your mileage may vary.
26Tudor - Very scientific! Also love the "T". Kinda like what I want to do to my Dad's '27 tudor if he will ever let me get my hands on it. Got a 348 W engine waitin' in the wings for that..
I've used that 1500 degree rated grill and oven paint in a rattle can. It worked well. I was careful not to over do it though.
Stop at our local hardware and get a spray can of Barbeque black. It's just what the label says it's for..........restoring the color on your old barbeque. Take a clean radiator and just give it a fog coat, your only looking to get a uniform covering as thin as possible. Don't use multiple heavy coats. if you can cure it with a heat lamp all the bettter. If not, install it and let the engine heat cure it. Frank
I powdercoat the tanks and spray the crap out of the cores, no problem. if it overheats after you paint it, you gots other problems.
Model A Vette, I too worked at a radiator shop when I was just out of High School. Painted them exactly as you described. Also used to dump Muratic acid into the necks after they were repaired then flushed it down the drain. It made the inside nice and shiny though. IMHO I don't think paint hurts it one bit.
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