painting an engine block

ksungela

Member
I'm making a proposal to someone who wants their '67 GTO painted similar to the car in the movie XXX . This will include painting the engine purple. Not sure yet if the purple will be a solid or metallic. I'm thinking the process would go something like this:

Degrease engine
Media blast (without any media entering internals of engine)
Wash again
Epoxy
basecoat or single stage
clearcoat (if not single stage)

Any opinions on this plan?
 
Clean, clean and clean again, you can never clean enough and when you think you are done, clean again.
No media blasting needed nor any sanding.
Spray two coats of un-reduced epoxy and next day paint as you wish.
Over the years I have done many engines and one failure, on wifes 312 two months later under the car and noticed a two-inch bubble in a corner spot, you just cant clean enough.
 
i use carb cleaner and sometimes ospho ( GASP) to get it clean. i have learned to keep the film build down .
 
Years ago, a buddy of mine did a lot of custom hot rods and would use spray cans of ether (diesel starter fluid) to clean an engine. He would then spray stage one color on the engine and I don't think he used any primer either. He must have used ether without any additives in it. I've noticed that the starter fluid from Walmart has some sort of lubricant in it. Just my 2cents worth.
 
What about on a engine that has rust all over it? Would you recommend blasting then?
 
I wasnt planning on tearing the motor down. This isn't a resto I'm just cleaning the truck up.
 
I wouldn't use any normal blasting media on an engine, I think they use steel shot when blasting engines, and phosphoric acid should not be used on cast iron. I have a stripper in my area that cleans everything with the electrolysis method, including cast iron, it cleans the block and heads completely inside and out.
 
Here's my backyard, shade tree, mechanic method.
1. Apply heavy duty degreaser, wait a few minutes and then scrape or wire brush the thick gunk off.
2. Apply heavy duty degreaser, wait a few minutes and then wire brush the remaining gunk off.
3. Mix some laundry detergent (Tide) and water. Use a scrub brush and scrub every square inch of the block.
4. Repeat step 3 until it is clean.
5. Use assorted wire brushes to clean crevices and oil passages. (I have found slag blocking oil passages before.)
6. Squirt some solvent based W&G remove onto the block and scrub with plastic bristled brush. Keep squirting 701 to flush the areas while brushing.
7. Blow dry with compressed air.

SEM carries most original engine block colors. It has worked well for me so I continue to use it if doing a restoration and not a custom job.

Front View.JPGLeft Rear View.JPGEngine Front - GM Blue.JPGEngine Rear - GM Blue.JPG
 
Wow thanks for all the quick responses. 68 coronet that engine looks great.
 
'68, where did you get the SEM engine paint? I checked their website and could only find 2 colors for marine engines.
SEM is a popular product around my part of N. Carolina and I have used a lot of their products, mostly with good results.
 
My bad, I had used SEM recently on some interior parts and had it stuck in my head.
The turquoise was Mopar Performance brand and the GM Blue was by VHT. :confused:
 
funny that in the 60's everyone used coca cola to clean up engines . i've used milkstone remover for at least 30 years to clean up engine blocks and such.
 
Is this directed at my post about not using acid on cast iron? I guess I should clarify.
Phosphoric acid dissolves cold rolled steel at a slow pace, the result is the etching that we see after the steel has been submerged for an extended period of time.
Cast iron has much more open grain and will dissolve much faster because its not rolled, its cast. Its similar to aluminum and pot metal, although not as bad. Just drop a chunk of cast iron waste in some phosphoric acid, leave it for awhile, and watch the stream of tiny bubbles come to the surface.

It just depends on how long the cast iron will be exposed to the acid, but I don't use at all on cast. It sure wouldn't be wise to dip an engine block in phosphoric acid. There is also the possible concern of hydrogen embrittlement.
 
he wants to clean an engine to paint. no one said anything about tearing it down and dipping it .
 
Like I said, it just depends on how long the cast iron is exposed to it.
A better choice is Evapo-Rust, it removes rust and is not acidic. Its safe on all metals, it does work a little slower than acid, but not bad at all.
 
Shine thanks for that tip about milkstone remover I can pick that up locally and it's cheap. Chevman thanks for mentioning it I would of never though of that. It won't be on the engine long enough to cause hydrogen embrittlement. It's an old 5.9 12 valve Cummins with oil all over it. But plenty of rust in some spots as well.
 
it dilutes with water . we use it to clean dairy equipment . i use it instead of ospho . cheaper.
 
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