Painting engine case?

Is it a bad idea to paint the magnesium engine case? What is the best type of paint to use?

Reply to
69 ground up
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..................There have been a lot of opinions posted here on this subject during the past four years that I've been around. So long as the cooling fins on the cylinders & heads aren't being painted, I don't think that what you do to the case matters very much. If it's not a new case, I wouldn't bother because the porosity of the case makes it likely that oily residue will get trapped under the paint and it will start coming off before long. Sending the case to get hot tanked might get rid of that problem. If you use an engine enamel that's good for 400 deg. F, it'll be able to withstand the heat. Most of the non-VW aircooled engines that I've seen on small airplanes as well as on motorcycles have bare metal cases.

Reply to
Tim Rogers

this is from an aircraft engine rebuilder site

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The overhaul process

"The engine is then painted with a highly durable, anticorrosive protective finish. "

69 ground up wrote:
Reply to
GreggH

On Fri, 10 Oct 2003 10:07:14 -0400, "Tim Rogers" ran around screaming and yelling:

Bob hoover as well as many other sources say that painting the cylinders with a light coat of flat black paint is a good thing...protects agains rust(which is an excellent *insulator*) and aids in heat transfer J

Reply to
Joey Tribiani

...................It is a common practice by some aircraft overhaulers to paint the case during a rebuild. Those engines come new from the manufacturer without anything on the case and if you walk around most any civil aviation airport, you'll see that most Lycoming & Continental engines aren't painted. These rebuilders want their customers to think that they're getting their money's worth when they fork over $10k+ and the paint helps to provide that 'effect'. There's really nothing wrong with this practice so long as it's understood to be purely cosmetic.

Reply to
Tim Rogers

.................my bad.

.........I forgot about that sermon. I've never painted a cylinder and my engines have never lasted long enough to get very rusted..........lol

..............Didn't Bob say something once about 'peening' the cooling fins of the heads to give them more surface area for better heat transfer? I'm going to be pulling the heads on my '77 this winter and I'm wondering about doing something like that to help run lower head temps next summer.

Reply to
Tim Rogers

Blast with coarse media, also good for cylinders(Only outside surfaces!)

J.

Reply to
BergRace

...............Would you still paint those cylinders after blasting them?

Reply to
Tim Rogers

A thin coat of flat black, does not constrain the rust for long though....

J.

Reply to
BergRace

Reply to
GreggH

.................Paint doesn't conduct heat as well as bare metal. As for corrosion blocking heat transfer, it's probably no worse at it than paint. Just my opinion.

..........I usually clean up a bare case with a 3M pad until most of the corrosion is gone. If it lasts long enough to get very corroded again before another teardown, that'd be a good thing........for me!

Reply to
Tim Rogers

A thin coat of NON-INSULATING black paint would be the best to use if you are going to do it. Mark Detro Englewood, FL

Reply to
Mark Detro

Yada, yada, yada. It really doesn't make any friggin difference what you paint the case as long as you don't lay housepaint on it. The case never gets hot enough to radiate into the significant infrared. Tim had the ultimate summary. Go there. Read what he wrote. Don't get crazy with some wild-assed, half-assed theories of thermodynamics unless you want to be bludgeoned by someone who knows his shit and has the time to drill it into your skull.

Reply to
jjs

Did someone take old Staffords beer again??

J.

Reply to
BergRace

Beer! Got to try some of that stuff one day.

So the presidents of Budweiser, Miller and Guinness go out for lunch. The Bud Prez says "I'll have a Budwiser". Mr. Miller orders a Miller. The president of Guinness orders a Pepsi. "Why did you order a Pepsi?", they ask. He says, "Well, if you guys aren't drinking beer, I won't either."

Reply to
jjs

So.......... I should paint it with Guinness then. A little for the case a little for me....a little more for me....a little more for me.........

Actually I have been resoled to the ole wire brush treatment. Looks pretty good. Experimented with a little sandpaper coarse to fine too (that may be over the top though). Whenever I decide to take a break I might even post some pictures of what is going on around here.

Thanks for all the feedback

Reply to
Eric Von Zipper

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