Parts Painting with Engine Orange _ what did I do wrong

[Donald H.]

I have Quanta's engine orange paint and am cleaning and painting some smaller parts. The first part that I tackled is the front engine mount bracket, which is steel and not cast iron.

I did some searching and found some references in this forum that folks advise not to use primer when painting the engine block (cast iron).

Here is what I did, I blasted the part to raw metal, sprayed with etch primer. Then put on a coat of Quanta's engine orange paint. I didn't get good coverage, so I waited 24 hours then sprayed another coat. The second coat caused a lot of alligator cracking/crazing. I'm also rebuilding the water pump and need to paint it. Since it is cast iron, I may just spray a lot of light coats to get good coverage and see what that does.

What did I do wrong?

I will call Quanta tomorrow, but am wondering if others have used the paint and know how to use it?

Thanks,

[Robert S.]

Re: Parts Painting with Engine Orange _ what did I do wrong

Just to be safe, don't paint the area of the waterpump where the radiator hose goes. Sometimes the antifreeze will soften the paint and the hose will slip off. Don't ask me how I know.

[Wayne W.]

Re: Parts Painting with Engine Orange _ what did I do wrong

I have never used any quanta stuff, but I would guess by the way it reacted, it is acrylic enamel. Acrylic enamel goes through a critical peroid that it cannot be re-coated. It needs to be shot within a short time period or you have to wait until it is fully cured to re-coat.

[Domenic T.]

Re: Parts Painting with Engine Orange _ what did I do wrong

I have Quanta's engine orange paint and am cleaning and painting some smaller parts. The first part that I tackled is the front engine mount bracket, which is steel and not cast iron.

I did some searching and found some references in this forum that folks advise not to use primer when painting the engine block (cast iron).

Here is what I did, I blasted the part to raw metal, sprayed with etch primer. Then put on a coat of Quanta's engine orange paint. I didn't get good coverage, so I waited 24 hours then sprayed another coat. The second coat caused a lot of alligator cracking/crazing. I'm also rebuilding the water pump and need to paint it. Since it is cast iron, I may just spray a lot of light coats to get good coverage and see what that does.

What did I do wrong?

I will call Quanta tomorrow, but am wondering if others have used the paint and know how to use it?

Thanks,

Donald,
There are some that say do not use primer and that's what I think went wrong.
Primer attatches to APX 50% of the metal and lets the paint attach to it and the other 50%. It gives you positive coverage.
Now the other view is that you should put a tack coat on first then follow with # 2 & #3 coat, that works also with much more paint and the chance of wrinkle and later cracking.
I have used rustolium primer under about 40 to 50 engines and have had NO problems.
Primer is exactly what it says (primer).

DOM

[Joe M.]

Re: Parts Painting with Engine Orange _ what did I do wrong

Same issues with Bill hirsch's paint if you don't follow the instructions to the letter. Must paint it the first time or wait forever to recoat.

[Chuck S.]

Re: Parts Painting with Engine Orange _ what did I do wrong

On parts fabricated from steel, I use DPLF90 epoxy primer. You must have a spray gun, compressor, and a respirator (IMPORTANT) to apply DPLF.

It lacks the convenience of aerosol cans, but you won't see any flaking either. DPLF is designed to be applied directly to clean bare steel, and chemically bonds to any compatible top coat if the part is painted within a week(?) of priming.

I have previously heard of top coat adhesion problems when using etching primers. From experience. I know that spray can enamel flakes off zinc rich primer as well...just because it says "primer" on the can doesn't mean that just any top coat will stick to it.

[Wayne P.]

Re: Parts Painting with Engine Orange _ what did I do wrong

I used Hi Heat primer first no problems so far. Good luck.

[Edward J.]

Re: Parts Painting with Engine Orange _ what did I do wrong

Don, sometimes you may get a reaction if the paint is lacquer and the other is enamel. or vice versa

[Mike G.]

Re: Parts Painting with Engine Orange _ what did I do wrong

Don, sometimes you may get a reaction if the paint is lacquer and the other is enamel. or vice versa

what he said. thats what it sounds like to me. sometimes the two different types will have a bad chemical reaction.

[Donald H.]

Re: Parts Painting with Engine Orange _ what did I do wrong

Don, sometimes you may get a reaction if the paint is lacquer and the other is enamel. or vice versa

I didn't seem to have the reaction between the primer and the paint. I primed with SEM etch primer, then a coat of the Quanta engine orange paint. That was fine, it was when I tried to put on a second coat after 24 hours that I had the problem.

I have sanded the piece enought to get rid of the crazing and will wait a week or so and then try another coat.

[Chuck S.]

Re: Parts Painting with Engine Orange _ what did I do wrong

I didn't seem to have the reaction between the primer and the paint. I primed with SEM etch primer, then a coat of the Quanta engine orange paint. That was fine, it was when I tried to put on a second coat after 24 hours that I had the problem.

I have sanded the piece enought to get rid of the crazing and will wait a week or so and then try another coat.

Sorry. I confused your thread with an earlier one on flaking and poor adhesion...I missed that part about alligatoring/crazing

If you Google "paint alligatoring", you get pages of sites (mostly house painting oriented) that explain alligatoring. The one with the best explanation http://www.hometips.com/repair-fix/p...igatoring.html gave this:

Paint Alligatoring When a surface is cracked like alligator skin, it usually means one of three things: the paint is so old that it no longer has any resilience to changes in the weather, a newer top coat didn’t adhere properly because it was not compatible with the primer or bottom coat, or, the paint was applied before a previous coat was dry.

A badly cracked paint surface should be repainted, but before you do this, you will need to remove the old paint. To avoid alligatoring in the future, make sure the paint you choose is compatible with the primer, and allow the bottom coat to dry completely before applying the next coat.


Sherwin-Williams has an automotive paint trouble-shooting site, but it's now an ashx file that I didn't download. Both of the likely causes for new paint problems have already been mentioned here. To eliminate both possibilities, I would bead blast the part back to white metal and start over with Rustoleum gray automotive primer.

You either (1) have compatibility problems (simply sanding top coat smooth may not eliminate) or (2) you didn't allow the first coat to fully cure. Paint instructions usually indicate a minimum painting temperature of 50 degrees, and may indicate 24 hours to be adequate drying time at 70 DEG.

[Edward J.]

Re: Parts Painting with Engine Orange _ what did I do wrong

Don, I used the quanta orange paint on my small block a few weeks ago and it was over the bare cast iron, I will say that the coverage off the newer paints do not cover as the older paints, the lead was removed many years ago -Hence the paint flow and coverage was gone. I find re-coating every 15 minutes work great til you get where the result your looking for.

[Wayne W.]

Re: Parts Painting with Engine Orange _ what did I do wrong

Its acrylic enamel, unless the additive is used, it will bust up if allowed to get into the critical period. Finish painting on the first round, or wait a long time for it to cure.

[Ronald L.]

Re: Parts Painting with Engine Orange _ what did I do wrong

Or buy the cheap stuff and spray away.

[Edward B.]

Re: Parts Painting with Engine Orange _ what did I do wrong

Factory never bothered with primer; why are we doing so fifty years later? Factory was dealing with new components, so it is probably a good idea to wipe everything clean of oil and grease, but beyond that just grab the rattle can and spray.