TheSamba.com :: View topic - Is painting your engine block all that bad?

Fri Mar 03, 2006 8:02 pm

I was wondering what some long term effects would be of painting my engine block. If anyone has some first hand experience I would love to hear it. Thanks in advance.

-Aaron

Fri Mar 03, 2006 10:42 pm

I have painted a few, just do a thourough job of cleaning the case before you spray it so you can obtain good adheasion and tape off the holes and spots where any gaskets go.

Sat Mar 04, 2006 7:05 am

It has been said that the engine case cannot breath when that happens.

Sat Mar 04, 2006 7:08 am

It's not that bad. But i wouldn't do it.

Sat Mar 04, 2006 7:17 am

On the case, it doesn't matter enough to worry about. Paint away.

Sat Mar 04, 2006 7:21 am

Paint holds in heat. Your engine is air cooled. Heat is your engines main enemy.

Sat Mar 04, 2006 7:32 am

I've done it on one and to be honest, even the high temp ceramic paint will blister when it gets gas on it. Probably not worth it in the long run. I'd prefer to polish one to make it easier to clean. Those rough casting marks really collect crud. But after reading about the poor guy who set himself on fire grinding a tranny I ain't gonna do that either.

Sat Mar 04, 2006 9:07 am

I'd rather spend the time to thoroughly clean a case. I've found that if you have a stained, dirty looking case you can give it a clean, fresh appearance by roughing the surface up. I've used wire wheels, flap wheels, etc. It'll give a bright look at first, but after a few weeks it'll tarnish and look like "new" magnesium.

I've painted cases, always hi-temp black, but the first drop of gas or brake parts cleaner and the paint will curl up and peel off.

Raw will always look better in the long run.

Sat Mar 04, 2006 2:29 pm

There is only a small portion of the block that shows, So why not paint just that? Best of both worlds, Cosmetics and heat dissipation. (spelling?)

Sat Mar 04, 2006 6:38 pm

Why would you paint something that is so easy to polish? I polished mine & have yet to regret it.

Sat Mar 04, 2006 6:56 pm

paint does NOT hold in heat..... painting is ok.. clean and mask is imperative, though, and flat black is the best paint color to RADIATE the heat originating from the case.
Other colors are ok, but black is thermally your best bet-other colors arent as effective, but honestly a hot pink engine is not going to run hotter than an unpainted case.

Sat Mar 04, 2006 10:09 pm

Depends on color and type of paint. Some colors and paints can actually help transfer heat quicker then being unpainted.

Painting for looks though seems kind of dumb since you wont be able to see the engine with the shrouds on anyway.

I didnt read the whole thread incase I missed something.

Laters

Sun Mar 05, 2006 3:31 am

shane red wrote: Why would you paint something that is so easy to polish? I polished mine & have yet to regret it.

I've only seen polished cases at Glamis. Shane Red, do you have a picture of you polished case? I'd like to see how it would look in a full bodied car.

Wed Mar 08, 2006 6:24 pm

industryvw wrote: shane red wrote: Why would you paint something that is so easy to polish? I polished mine & have yet to regret it.

I've only seen polished cases at Glamis. Shane Red, do you have a picture of you polished case? I'd like to see how it would look in a full bodied car.

Hell yeah, it's all dirty right now but I'll go snap a pic.

Thu Mar 09, 2006 4:34 am

And how did you polish it?

Thu Mar 09, 2006 9:54 pm

As far as how much paint affects the engine I am not sure, but to clear up some of what has been said here is the short of it. A flat balck paint will radiate more heat than any other type of surface finish. That is why all the engine tin is flat black, and if you are going to paint your block then that would be the best color. The colors get worse at radiating heat as they get lighter. Now the worst thing to do would be highly polish it. A shiny finish will be the worst radiator of heat possible. If you are going to paint it you also want a very thin layer of paint or a chemical method of applying the paint, because the thicker the layer of paint, the thicker the layer of insulation you just added to your engine. Paint holds in heat in effect the same way as letting dirt and grease pile up on your block...it just impedes direct airflow. In reality all this might only add up to a few degrees since most of your heat is in the cylinders and heads anyway, but this is the theory behind it all. Hope this helps.