Painting an engine.

I didn't want to hijack chevygirl396's thread on painting engines so I thought I would just do a separate thread on how we painted my Son's Olds engine today. As I mentioned in her thread, we have always used epoxy primer and topcoated it with our favorite brand and color of paint, and do it exactly as you would paint anything else, such as a car body. The paint holds up to the heat just fine and lasts for years if you do it right.

While you can paint an engine that is all assembled, and we have done that, my Son Dan likes to paint them in pieces, so we paint the block, the heads, the intake, oil pan, and parts like that separate from each other then will assemble them when they dry. The reason he likes to do it this way is so the paint isn't covering gaskets and if you ever need to remove a head or something it won't pull any paint that is stuck over the seams.

The engine was originally painted black when we first built this car but this time around he wanted to do it in a gold like they used on early Olds engines. Yesterday we went to the local auto refinishing supply shop and picked out a Dupont Imron fleet gold color that we felt was close to the Olds color, as well as some Dupont epoxy primer and appropriate hardeners.

Dan spent all day yesterday prepping the block with a roloc disc, then cleaning it with laquer thinner and a stainless steel brush. He also spent a lot of time masking off the areas that don't get painted. That was the most time consuming job, it took him probably 8 hours with blue masking tape and an exacto knife, but it pays dividends as the job comes out much better and neater.

Today we had nice warm weather and we got all the parts moved out into the parking lot so they could be primed and then painted. Here are some pictures of what the parts looked like in bare steel after the final wipedown with wax and grease remover.

Don

The next step was to prime the parts and Dan laid on one medium and one slightly heavier coat and let that cure for an hour. Here are some pictures of the same parts primed.

Don

After the primer flashed for an hour Dan topcoated it with two coats of the final gold color. We like Imron a lot, it is easy to spray, flows in nicely, and it tough as nails. Here are the parts with the final gold color applied. Of course, we had to push the motor in front of Dans RPU body to see how the gold went with the black body and off white firewall. I think it will make a real difference in the look of the car.

Don

A vast improvement Don, I never liked the black engine, now it will really make the motor stand out, top job :3dSMILE:

Looks phenominal, cant wait to see it all assembled

Don very nice paint job and a great description on how to do it with engine apart. Have you ever painted and engine while still in the vehicle? If so do you have any pointers on that? Bart

Don is that Imron paint a 2K ???

Don, it looks really good. I like to paint them dissembled too, besides the points you bring up I think it really brings out the detail of the engine.

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Originally Posted by roadster32

Don is that Imron paint a 2K ???

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imron is a dupont line that is or was more or less mix off a hopped up acrylic enamel mixing bank with a poly urethane fortifier and a imron harder. it then is a some what poly urethane paint not a true polyester poly urethane paint .if you can not find it whats is has good if not better was a PPG line called star thane same thing mixed off a ppg enamel mixing bank then there is Durathane a true polyester poly urethane but colors are very limited .true urethanes use a true urethane mixing bank as true polyester urethene line up. many paint makers do or did at one time use enamel and hopped it up for a fleet /industrial paint i shot many of them :) looks good Don .do not get mad ... not to sure about painting over the intake gasket surface

that does look really good. good point on painting them assembled i never thought of that and we were planning on painting it put together. i think i will paint it while its apart now. thanks for posting the pictues too!

Thanks all. Bart, no, never done one in the car except years ago when I had cars that I just wanted to make the engine room look better, so I would mask off everything and would spray can the engine. If you take your time, get everything really clean, remove as much as you can, then mask and spray, you can get a pretty decent job.

Pat, no offense taken, we had the same discussion, especially because of his last sealing issues. But he wants the areas around the intake to look as finished as possible so he decided to shoot the entire manifold to head mounting surface, then we will lay a gasket on it, trace around it, and scuff the hidden areas real good with scotchbrite pads. I think if we do that, use some good composite gaskets, and some good sealant, it should hold a seal. We are not going to use the normal tin pan gasket that they make for these 455's, Mondello told me they see a lot of problems with those sealing.

We didn't paint the intake manifold yet because we are going to take it to the machine shop for surfacing, or at least to see if it needs surfacing. We were getting some areas the last time we mounted it where it looked like some areas were not touching as much as others. Don had some minor sealing issues with this same intake years ago when he ran it on his 65 Olds convertible, so there might be some irregularities in the gasket surface. Once that is done we can sandblast it back to bare metal and do the same priming and painting as on the rest of the engine. He also wants to change the transmission color from black to this gold too.

We did find one downside to painting an engine with the epoxy primer and Imron system..........we forgot how expensive it is. We walked out of the paint store yesterday with the primer and it's hardener, the Imron and it's hardener, a few plastic cups, and the bill was $ 236.00. :eek: The local paint supplier only carries the Imron 192S hardener in quarts (we needed a pint) and that alone was $ 110.00. I think it was only about $ 75.00 the last time we bought the same product.

Don

I agree with Pat about painting not only the intake surfaces but any surface that gets a gaslet or seal--REPEATEDLY when we are dealing with some one who has a vacume leak or oil drip its because of painted surfaces--In todays chemical world there is no way you want to mix paint and any gasket sealer and hope for a seal-----------

Also regular(not hi temp ) paint will burn off the exhaust port areas, especially Olds,FE fords, Cadilacs--any that the port area is sort of raised and extended

on a painted intake side of head i wipe clean with lacquer thinner then 2 inch masking tape. for intake lay a intake gasket use bolts to line gasket on head draw a line around gasket then cut with a razor knife peel off the tape off were you want painted. peel tape off when paint is still drying .less is better so you do not end up with a paint lip . etch prime just till you can not see threw it same with paint

That does look real nice,Don..Much prefer a gold to the black engine..I have used the DuPont system myself,,and a fair bit of Imron,on various things,,like the chassis under Lyndas Customline,suspension parts etc.Darn good paint..The only drawback I have found is the cost..Cant remember what I paid,,but with the exchange rate we have(to the US $)it seems similar in price..

Thanks Robin. Jerry, I appreciate that feedback about the sealing. It was a tradeoff somewhat as he really hates void areas in the finishes, so we decided the only way to really get a clean edge was to paint it all then roughen the gasket area only . He was also looking for a gold sealant so none would show around the gaskets. :LOL:

We'll see how it works out and if it leaks at all we'll remove the paint entirely in the gasket areas only, at least around all the intake and water ports. In fact, now that I think about it, we will remove the paint around the ports before we aseemble it for the first time.

Don

From past experience, paint doesn't seal...it's too smooth a surface to get any mechanical adhesion, and chemical adhesion won't be there cuz the sealant can't chemically bond with a painted surface....