I hope you can give me some sound advice to get my engine prepped properly for a good paint job.

I have an engine I purchased from a friend (he needed the money more than I needed the engine). The machine shop tanked the block and painted it using something similar to cast blast just to prevent rusting until it could be painted permanently.
I was worried about using this paint as a base because I wanted to use an etching primer, so I removed some of the paint and I see a light but very noticeable amount of rust.

How do you go about removing the paint and rust from an engine that has the heads, pan and timing chain cover installed?
I’m especially worried about using a paint stripper because of what it would do the gaskets. Removing the pan, timing chain cover is no big deal but I don’t want to remove the heads if it can be avoided.

Any advice is appreciated.

Gary

 

Those flexible abraisive wheels that fit in an electric drill and wire wheels will certainly do it, but will take a while. Obviously the engine must be sealed up tight to keep any abraisive material from getting in. You can then go over it with something like Dupont metal surface rust removal treatment before painting.

Dan

 

You could also use a Dremel for the smaller areas.

 

if it helps.....
last winter I painted the motors from both my '65 and my '78 vettes.

since the motor you are dealing with is out of the car (I assume) I'll relate how I did the motor from my '78 which I had pulled and had on an engine stand.
I had removed everything off the motor except the heads, balancer, waterpump,timing cover and oilpan.
I taped over the lifter valley and plugged the exhaust ports of course and kept the old sparkplugs in to keep the chambers protected since I was going to replace the plugs anyway. I used aluminum foil to cover the valves since the valve covers were off.

I stripped off the old paint with spray on paint stripper I got from Pepboys (Aircraft stripper I believe). Let it soak in for a while, sprayed on my stripper and again let it soak in and soften the old paint. using a plastic scrapper and wire brush and spray carb cleaner got most of the old paint off.
After the black was stripped of the old paint I wiped it clean from the chemicals with first lacquer thinner than PPG Acyli-Clean (a pre-paint cleaner).
I used the hi-temp engine paint from Hirsh Automotive which is really nice stuff. They specifically recommend NOT using a primer on the iron block as they say that their paint adheres better to the bare iron metal of the block without primer although I did use a few coats of primer on the steel oilpan and timing cover. I was surprised to hear them recomment against use of a primer but I figure they know their own paints best so I did as they recommend.
After priming the oilpan and timing cover I simply painted everything with the hi-temp engine paint. I did 2 very light coats at first than 3 medium coats.
It came out looking great and the stripper didn't have any negative effects on any of the gaskets such as the oilpan, waterpump, or mainseal gaskets.

here are pics of the motor after pulling it thru the end of painting it.
http://69.253.166.197/corvettes/page...8/page148.html

 

POR15 makes an engine painting kit that includes degreaser, metal prep, primer, and finish coat. It can go over old paint and rust. I painted an engine with it a year ago, and it still looks as good as the day I finished.

 

Thanks everyone for your input!

Barry, were you concerned about the stripper getting absorbed by the edges of the head or timing cover gaskets? That was my concern. I thought the caustic stripper may breakdown the gasket or be absorbed and eventually cause the paint to loose adhesion.

I like your idea.

 

Gary
to be honest the thought of the stripper effecting the gaskets never even crossed my mind.
I got the idea of using the stripper and the carb cleaner to strip the block from prior posts on here from others, it sounded reasonable and easy which it was, and it worked well. Like I said the effect of the gaskets never crossed my mind and was never mentioned in the prior posts as an issue. Besides, the stripper only sat on the motor soaking into the old paint for 20 minutes or so and afterwards the lacquer thinner and Acryli-Clean would have neutralized it.
This was done back in the Spring (March) and I have zero leaks from any gaskets so i'll have to assume there was no negative effects from the stripper.
The stripper shouldn't cause the new paint to lose adhesion as long as it's thoroughly cleaned and washed off after the stripping and before painting - same as when a body is chemically stripped before painting.

 

Barry

Thanks I'm probably being overly concerned. I think I'll give your process a try. I've used some great spray on type paint remover from PPG. It's water soluble and like you said it probably won't be on for long
I'll let you know how it works out.

Thanks again