Painting aluminum
 

I am in the process of rebuilding my egnine and I not sure how to prep and paint my aluminum pieces: valve covers, tappet cover, oil pan. I've soaked them in Simple Green and hit them with brakekleen. The grease and grim came off but there's a lot of stains on them. Should this be sanded off or will the primer conceal it? Do I need to do anything else?
Thanks for any help.
Joe

Re: Painting aluminum
 

When I converted the 1974 SBC I am putting in my '65 C10 to a serpentine system from a 90's Chevy truck I was focused on running the aluminum brackets in polished form. I did what you did to try to get them clean before polishing them and found some stains just would not come out no matter what I used to clean the metal. In the end, I just used some paint prep degreaser, engine primer, and then engine paint to paint the brackets black. It went down nicely and has stayed put without imperfections over the entire brackets including the stains I couldn't get out.

Re: Painting aluminum
 

I had some aluminum engine brackets blasted. The company I use is really good and just cleaned them up to look as close to stock as possible. I'll probably run them as is without coating them with anything, but could easily paint them now.

Re: Painting aluminum
 

I've painted a few smaller parts by blasting with aluminum oxide media, acid etching with aluminum brightener, the immediately priming with either self-etching or epoxy primer.
I think the hardest part of painting an entire aluminum engine would be getting all the oxidation off and getting it clean enough for the paint to stick and stay on over a long period of time.
I debated painting my aluminum LS but ultimately just cleaned it and left it as is,
after all it's not going to rust....

Re: Painting aluminum
 

For driver quality, sand and scuff them, as best you can. Clean with thinner and use a quality rattle can. For show quality or long term durability. Sand blast, clean with thinner, epoxy, prime. Then top coat with a 2K single stage or base/clear.

Re: Painting aluminum
 

I've had very very good luck with StarBrite aluminum cleaner. It's made for the marine industry, specifically cleaning aluminum pontoons.

https://www.amazon.com/STAR-BRITE-Ul...s%2C120&sr=8-5

Re: Painting aluminum
 

I do what 62c30 and A1971 Blazer do. Clean them then lightly sand blast. You can use a self-etching primer if you want and they will hold paint a long time.