98RedBird

iTrader: (77)

I have the block out and attempted painting it right after it was hot tanked and cleaned. I painted it black with the Duplicolor High Temp engine enamel. I let it sit for about 2 weeks and when I was messing around with it getting ready to start putting it back together I noticed that the paint would flake off and chip very easily. I'm not sure why. I did not use a primer or a clear. Would this make a difference? I would really like to paint the block, timing cover, oil pan and water pump black but not if it's going to chip and flake off. I want it to be somewhat durable. I got some automotive paint stripper and am pulling all of the paint off at the moment. Should I get it cleaned up again and then go back together with it without painting or should I try and paint it again? I don't want it to look like **** here in a few months because that would be nearly impossible to fix once the motor is already back in the car....

What do you guys think? I also heard that painting the aluminum block is not recommended, why is this? Also, when painting the engine, and accessories what do you guys to about where the bolts go in? It will break and crack the paint when you torque the bolts down wont it? I'm just trying to decide if I should try to paint it again or just leave it bare aluminum.

Thanks,
Drew

Brian2006

iTrader: (42)

I don't know why painting the block isn't recommended because that's all they did in the 60s and 70s. Did you by chance use duplicolor's enamel paint? You need to verify the paint is intended for aluminum and that the block is extremely clean.

J&J Motorsports FL

iTrader: (16)

I usually use some self-etching primer to paint over aluminum, but with painting engine blocks(usually iron) I just used engine paint primer. Without primer there isn't much for the paint to stick to.

Jeremiah

iTrader: (5)

Clean, clean, clean and use a good self etching primer like Du pont Vari prime or PPG DP sealers. Then use a good quality base/clear finish since the clear is far more durable and will resist chemicals/stains and will hold its gloss better than any single stage.

I painted the engine in my wifes old 69 Camaro over six years ago and it still looks like it was just painted.

Throw that rattle can crap in the trash, its all junk.

98RedBird

iTrader: (77)

Really, I heard that the rattle can stuff was just fine for this use.

J&J Motorsports FL

iTrader: (16)

I done a bunch of rattle can paint on blocks but you have to use primer, engine paint and engine clear. There is a decent self etching primer available at most parts stores that should do the trick.

Jeremiah

iTrader: (5)

A good quality base/clear finish is several times more durable and resistant to chemicals than any rattle can finish. Rattle can finishes lose there gloss and discollor in very short time... I know, I have used them all.

Like I said, the engine in my wifes 69 Camaro still looks like it was painted yesterday even after six years of operation.

I also painted the engine in a friends 70 442 Olds to match the stripes. He had the block vatted and rebuilt a couple of years after it was first painted. Other than a few scratches from the machine shop it still looked like new.

You simply cannot duplicate those results with any rattle can finish.

BIG_MIKE2005

iTrader: (116)

Yea, but not everyone wants to pay another couple hundred dollars for a custom paint job on a engine block. I have seen good results with the Duplicolor stuff. Hell even my brake calipers are still shiney when cleaned up & they get used aolt in my 300+ miles a week commute. I did them over a year ago. I see nothing at all wrong with the Duplicolor stuff as long as you do good prep work, use the specified primer, paint according to can & hit with some clear.