7 Fin Valve Covers

[Jorn J.]

Hi

I will shine up my valve Covers and wants to know how the best way doing such? I want to have the "original" look not shinny or so

Regards Jorn

[Jack H.]

Re: 7 Fin Valve Covers

You can't really get there... When factory fresh, the valve covers were 'as cast' repleat with the unbroken texture left by the casting mold.

When you 'polish' them, you destroy that texture and visually alter their factory originality. There are a couple of 'tricks' associated with cleaning up used original valve covers to make them 'appear' to be factory fresh though.

One is to use a form of oxidation removing chemistry like the ALUMINUM rated version of Naval Gel to clean the outer surface. You lay down this jelly like form of phosporic acid GENTLY with a toothbrush, allow it to soak/etch, and GENTLY rinse the part clean under warm running water following the manufacturer's recommendation(s).

Attempts to polish, scrub or media blast the surface clean almost always result in visual distrubance(s) to the 'as cast' surface texture of the valve cover.

Once, the part is clean and oxide free using chemistry to lightly etch, you may find 'spots' where dirt/oil have invaded the surface. These can be stubborn and REFUSE to clean up to match adjacent surfaces...

In this case, a 'trick' is to simulate fresh aluminum. One way to do that is with a decent quality aluminum paint and a toothbrush.

Dip the toothbrush into the paint and GENTLY scrub the discolored surface area using erratic motion to RANDOMLY spread the paint and work it down into aluminum. By moving in erratic directions, you attempt to spread the paint SO THINLY that there's no tell tale evidence of the coloring work (brush strokes, Etc.).

Get the paint on too thick? Go over it again with a spritz of paint remover and the GENTLE motion of your toothbrush.

A savvy judge CAN detect a 'botched' re-color job from an NOS 'as-cast' aluminum part. But, if you take your time and work at restoring your original valve cover(s), you'll find you can get pretty 'close'...

Another 'trick' is knowing what the original surface should look like repleat with its as-cast texture. Consider simply washing the valve cover clean with solvent and looking at the BACK side of the cover that did NOT see human touch over the years!

[Tom P.]

Re: 7 Fin Valve Covers

Jack,
I always wondered if the ORIGINAL, as installed during factory production, valve covers looked the same as the service replacement valve covers, which were available from GM for MANY years??? When pulled out of the unopened, GM box, did the dull luster and texture match that on the St. Louis built cars?
The reason I ask, is because if anyone has a set of NOS/virgin service replacement valve covers, then that finish is an excellent finish to shoot for (I'm sure that one or two of you have a set somewhere in the back corner, I do).

[Jack H.]

Re: 7 Fin Valve Covers

The only difference between what you see in the surface texture of an NOS valve cover and a factory original is the oxidation build up from having sat in box/on-shelf for +40 years... Texture should be identical, brightness should be 'slightly' dimished from the years of sitting in box.