painting the heads

tbsstunta · 10-13-2005, 04:40 AM

I searched but couldn't find the specific reference.

I want to do my valve covers up black, and I know someone on here used some inexpensive high-temp rattle can paint. what was it again and how is it holding up? How did you prep the surfaces?

Cheers

Trex · 10-13-2005, 05:20 AM

Haven't done it on the oilhead, but on an old airhead, I made sure the surface was grease free and I used some VHT (Very High Temp) header paint from a local speed shop.

From what I know, there are one or two steps to keep in mind when removing the oilhead valve covers. One of the latest issues of MOA covered the proceedure. I think it noted that you do not want to completely remove the (4?) bolts that secure the head. In that case, while painting, pull those bolts out and mask them. Unless you want them painted, also. I think a black head with silver bolts would look good.

For prep, I wiped out the inside of the head so weeping oil doesn't get in the way. The heads had about 25,000 miles on them so I used a degreaser from Pep Boys to remove the gnarly stuff. To clean that Degreaser residue off, I cleaned and scrubbed with Dawn detergent. I let that dry for a day or two and then used a paint prep solution (Griot's) and let it completely dry (this was a winter project. I did put plastic bags over the exposed valves on the bike).

I didn't use a primer, although if I had thought of it, I would have used a VHT primer. I shot a light coat of flat black header paint. I let it sit while the oven warmed up. I put the heads in the oven at 300-350 degrees for an hour. Let them cool off for an hour or so. I did that a few times over the course of two days until the heads looked nice and finished. I didn't sand or buff anything down. Since it was a 1977 100/7, with the horizontal fins, I did grind off the paint on those outer fins for a nice, striking look.

The finish never got bad over the next 25,000 miles that I had it, but it would get faded here and there and part of the Spring ritual was to just touch up the heads (n situ) with a shot from the spray can.

On some oilheads, I have seen a nice contrasting color for the plastic spark plug wire cover. For that, make sure you use a spary paint specifically for plastic. Plasti-Coat makes such a paint and should be available at Pep Boys.

jduke · 10-13-2005, 10:38 AM

Would heat retention be a problem?

JonyRR · 10-13-2005, 10:58 AM

'Would heat retention be a problem?'
no; they're ALREADY powdercoated (heat-retaining coating) silver

One COULD sandblast (with walnut shells for the right rough surface grain) and then kalgard gunkote them. Kalgard is the only coating I know of that actually, really, real-life-tested, cools and dissipates heat (including hi-temp flat black) over unpainted, uncoated, rough-surface-texture raw aluminum. part of the process is the blasting procedure which microscopically increases total surface area for more exposed material to dissipate the heat....like increasing the fin area on a strictly-aircooled engine. These oilheads are exactly thet...cooled by air-OIL techniques. I've always been of the opinion to get an R259 to run cooler you need a BIGGER oil cooler...as the oil dissipates most of the heat these things produce (and these things live and die by the quantity and quality of their oil *start the rant about another oil theread here*)
FYI, YMMV, etc...

jduke · 10-13-2005, 11:31 AM

A friend of mine bought a Buell Ulysses. While we were out Sunday riding, everytime he would stop you could hear a fan/pump running. He said the dealer told him because of the heat in the rear cylinder, they have an oil pump that runs until the heat drops to keep from cooking the oil in the head.