Cleaning L-98 Valve covers ??

[Tom S.]

What will work to clean the magnesium valve cover's on an 88 ? I am sure there is something that will clean them.I bought a product called brown royal at the NCRS meet at Old Town that was supposed to work but it made it worse!Any ideas that work will be greatly appreciated! Thanks in advance Tom

[Jim T.]

Re: Cleaning L-98 Valve covers ??

Looking forward to any answers on cleaning the vavle covers. My 85's need cleaning and repainting.

[Tom S.]

Re: Cleaning L-98 Valve covers ??

I tried the paint on an old set. It did not work. These covers absorb almost anything and look crappy after they are stained. There has to be some kind of chemical that will take the stains out! I don't know what but there has to be.

[Duke W.]

Re: Cleaning L-98 Valve covers ??

I did some research about 10 years ago trying to help a friend figure out how to keep the magnesium wheels on his GT-40 in decent cosmetic shape.

I queried around aerospace community materials engineers since aerospace uses a lot of magnesium castings. How can such be finished to protect them from corrosion and cosmetic degradation of the surface?

I came up blank. Surface oxidation is not a big deal on a structural part or gearbox casing, so apparently the aerospace industry doesn't use any coatings on magnesium components. The rapid oxide buildup on the surface is what protects magnesium from serious corrosion, but it looks like hell.

That said, there was a magnesium wheel option in the early C5 era. I'm quite sure they had some kind of coating, so there must be some process out there.

It would be interesting to find how these have held up over ten years. Not to many were installed. It was an expensive option.

The bottom line is that magnesium is not a very good material choice in an application where surface appearance is important.

Duke

[Joe L.]

Re: Cleaning L-98 Valve covers ??

Tom and Jim-----

I don't think that there's any way to "clean" the finish on these valve covers. The deterioration is not confined to the surface; it's right into the "paint". The only possible way to restore these that I could ever see would be stripping and re-coating. I don't think that these covers were ever painted, though. I think that it was some kind of "hi-tech" coating. It didn't prove to be very durable, though.

[Tom S.]

Re: Cleaning L-98 Valve covers ??

Thanks for the input! No the surface was not very durable, I have 13k on this 88 which is about as close to new condition as you can get. And the valve covers are a real detraction ! Look like crap! Does any one know if you can buy new ones? Thanks Tom

[Patrick H.]

Re: Cleaning L-98 Valve covers ??

I stripped a set, and it appears to be some type of powdercoating or similar. But, as you know, it has a definite texture, not smooth.

If you know any professional powdercoating shop that is willing to work with you, you "might" be able to replicate the finish. That's the only thing that comes to mind based on my experience with them. I Googled "textured powder coating" and apparently this is something that is done by many shops.

Patrick

[Joe L.]

Re: Cleaning L-98 Valve covers ??

Tom------

They're GM discontinued. However, you might check in an Eckler's or Mid America catalog. It seems like I saw these in one of them. They may have some sort of deal with GM's original source. I know they both have the paint, but, as you've found, the paint is not going to do you much good.

The valve covers on my 1992 still look near-perfect. However, anticipating the eventual discontinuation of the original covers, I bought a spare set a long time ago.

[Tom S.]

Re: Cleaning L-98 Valve covers ??

Joe
I have tried Ecklers and they have only the right side. I will try mid America though. I need only the left, but would take bought if I could find them.Luckily I only sprayed the left side! If you can call that luck! Tom

[Mike G.]

Re: Cleaning L-98 Valve covers ??

you can buy L98 valve cover paint. i think i got mine at mid america. looks like new covers. i painted mine before flight judging and it did fine.. they turn brown over time so you have to do something.

[Mike G.]

Re: Cleaning L-98 Valve covers ??

all u can buy is one side. i think its the right side with the oil cap.

[Tom S.]

Re: Cleaning L-98 Valve covers ??

Yes Ecklers has the right side available. It seems strange that there are no lefts available. I have not tried the paint from Mid America, but I have tried Ecklers, and it did not work, they looked worse.I will check mid America, maybe they have something differant! I would realy like a set of new covers!

[Mike G.]

Re: Cleaning L-98 Valve covers ??

they only make the side with the oil cap. i guess they figured you could live with 2 oil caps so the saved the money and only make the cover with the hole.

[Pete B.]

Re: Cleaning L-98 Valve covers ??

I have 2 C4's, did both in the last few months. I went to Auto Zone and got the Krylon high heat aluminum paint. I washed the parts in hot water and scrubbed them lightly with a medium (red) scotch brite pad, then a final wipe with acetone. At first they looked too bright but after a few days and the handling during the reinstalling them, they look great and original.

[Tom S.]

Re: Cleaning L-98 Valve covers ??

I did get the part #s, they are as follows L.H. side 10055781.. R.H. side is as follows 10055782. I have not found any L.H. as yet but have not given up! Tom