BC

Was there a consensus that I missed on what the underside of a newly sandblasted cam cover is supposed to be coated with so as to avoid any absorption of the oil into the material, possibly compromising the top side?

The other issue is the same, but different: The constant oil bath from the heads would break down most coatings.

Or is this more of a "Just put the damn things on" Brendan situation.

Just need some detail analysis on this for any BTDT on people who have:

Not coated them and had no problem later on (way later on)

Not coated them and had a problem with absorbtion

Coated them with some separate form the PC process (because I just redid mine, and I don't want to go back a third time) and it sticks just fine

Mrmerlin

Mask off the oil vent holes, Powder coat the outside, then put em on, you may find there isn much of a factory coating on the 32 valve covers just some overspary and thus it peels off and gets into the engine. Dont use a clear coat unless it has been tested on hot parts some types seem to yellow

Dave H.

a local shop sprayed a teflon "oil shed" coating on the inside of mine...

Giovanni

Two years ago I powdercoated both sides and recently I took them off to coat them a different color. The inside has held up pretty good.

Imo000

Don't coat them, leave it bare. Less of a chance of peeling and the chips getting into the engine.

I've worked on many different engines over the years and besides the 928, I haven't yet seen aluminium valve covers that are painted on the inside. I never seen oil ever seepign through either.

BC

Thanks guys. This would be the easiest, as they are already powder coated on the outside (again) crinkle black. The inside is now, as I said, just bare sandblasted (whatever the metal is - magnesium?)

These suggestions would make the job easier - doing nothing.

BC

Was this a Powdercoat or a wet paint?

BC

Interesting.

Tom in Austin

Wondered about this myself. When I refinished my cam cover, I baked in the oven to "out-gas" the metal. However, on the inside surface that seemed to have darkened whatever was there.

Even after power-washing the underside, I imagined some sort of soot or ash coming off in the hot oil spray over time.

atb

I sand blasted and outbaked mine. Painted the underside with buzz bomb hi-temp primer and hi temp gloss white. It's held up fine after at least 4 years and 20K + miles. It's cool when you pull the covers off to see the gloss white underneath, very "surgical".

largecar379

you could use block sealer, as used in drag race engines to facilitate rapid oil drain back......

although I don't think it's critical in your case.

then again, if you are going that far.....you might as well de-burr the block, heads, girdle, etc....


(no offense)

--Russ

RyanPerrella

LEAVE IT

dont paint the inside of the cover, dont powder coat it, just a complete waste of money.

as Russ said there is some type of oily goop that is reddish colored i think that those nascar dudes use, supposed to seal porous materials and allow for nice oil drainback, but still, completely unnecessary for the bottom side of a cam cover.

Giovanni

What is the coating Porsche used for the underside? It looks like they powdercoated the whole thing and the part exposed to the hot oil got a "tan".

6.0-928S

Engine builders use Glyptal. $50.00 quart.

"Recommended by many high performance engine rebuilding books, Glyptal seals the tiny pores left in metal after bead blasting and leaves the engine block interiors smooth. Helps keep the oil clean and flowing freely. Acid and oil resistant. Used on generator and alternator armatures, Glyptal has great electrical insulating properties, too!"

Hammer

ibkevin

Yep... it get's bathed in oil


only after you put it together and it runs.