paint the head gasket silver?

[saridout]

i'm reading along in my engine rebuild book, and it says that i should paint my gasket with aluminum paint if it hasn't been already. i got my gasket from MSA, and it seems to not have any coating on it. is painting necessary with newer gaskets? what do yall think?

Edited September 4, 2009 by saridout

[MikeW]

I could understand it if this was talking about using a copper head gasket spray sealer. However I wouldn't call that paint. Is it perhaps talking about painting just the edge that is visible between the block and head to match the head color?

[saridout]

the book says, "to seal a head gasket, coat it with high-temperature aluminum paint, copper coat, or equivalent."

[whamo]

I have used silver metalic spray paint on engines that had repeated headgasket failures and it does work. I'm fairly sure coppercoat would have the same effect.

[Phred]

Yes indeed, painting a head gasket is an old trick to get it to seal up. The reason for silver paint, is the paint base is, at least it used to be, metal composition with a bonding agent that will melt into the surface of the head/deck when the enging gets hot. For best results, find the best quality silver paint, as it will have more base color. Then just befor you install the gasket, spray two coats on both sides. Install the gasket when the paint is just starting to set. This will work on all types of gaskets. To make sure the paint sticks, wipe down the gasket with acetone befor painting. I was shown this trick forty years ago. Who knows how long painting head gaskets has been around. My guess is that long ago, an engine builder didn't have any real gasket compound, and the only thing he could find in the shop was a can of silver paint. Turns out it was a great find.

Phred

[MikeW]

So the question then becomes how does the silver paint compare to commercial products specifically made for spraying head gaskets?

[sblake01]

I've used Permatex Copper on head gaskets for about 40 years now without problems.

[Phred]

I have used just about all types of commercially available gasket sealing compounds. Most of them work. Some are easier to apply than others. If you just need to use it for one head gasket, and not take it apart again, just about anything will work as long as you follow the instructions. The silver paint things I like best are, price per gasket (you can paint a buttload of gaskets with one can). Reuseable gasket, if you really can't find a new gasket on the weekend you decide to take your head off. Generally, a painted gasket will come off without destroying it if you're carefull. For this reason, I always paint racing engine head gaskets, If you have a problem, and have to remove the head at a race, you can wipe the old paint off with laquer thinner or acetone, Paint it up again, and your on the track again. I have used a painted, stock Datsun head gasket on an 'O' ringed deck with 13.8:1 compression on a GT2 engine, and it sealed up fine. Whatever sealer you use, don't over goop it on, and let it drool down the side of the block, cause if it does, it is probably drooling down in your engine cyl. and cooling passages too. There are a number of good sealers, and a lot of people have used them sucsessfully. Be neat about it and it will work good, and look good.

Phred

[peterc]

Nice write-up. thanks Phred.

[saridout]

thanks a lot phred, that's exactly what i needed to hear

[saridout]

ok, new question. now that i've snapped a headbolt off in the block (no worries, i got it out), how do i get the copper spray OFF of the block and head? acetone? also, would using the same head gasket again not be recommended?

[Phred]

I use rubber gloves, acetone/lacquer thinner, and a scotchbrite pad. When all the old gunk is removed, wipe it all down with a fresh lint free towel dampened with a just a bit of cleaner. Then the paint will have a nice clean surface to stick to. Whenever you have a choice, always use a new gasket. I will only reuse a head gasket if I really don't have any other option.

Phred