Pagoda SL Group

W113 Pagoda SL Group => Drive train, fuel, suspension, steering & brakes => Topic started by: Harry on June 21, 2023, 11:35:28

Title: Valve Cover Finish
Post by: Harry on June 21, 2023, 11:35:28
Just checked valve clearance on my 1966 230SL, and was curious how you might improve the finish on this item?  I’ve seen some that are even shiny, and wonder what are the best methods to restore to the “new” finish or better?

Thanks!
Title: Re: Valve Cover Finish
Post by: JamesL on June 21, 2023, 13:02:31
Valve-train cover was matt ally originally
Shiny is  liked by some but a flat matt is, I believe, what came out of the factory
Title: Re: Valve Cover Finish
Post by: mdsalemi on June 21, 2023, 16:58:17
Harry, my engine came back from Metric back 23 years ago looking like "new" from the factory, without the glitz and glamour of a high polish. They just did everything right. I suspect it was a chemical cleaning with some kind of aluminum brightener. You may want to call them and see what they do.

Here's a before and after. They not only did a great job of making the engine run well, they made it look proper too. Hence the suggestion to call them.
Title: Re: Valve Cover Finish
Post by: gh356 on June 21, 2023, 19:46:46

Vapor blasting cleans aluminum beautiful, giving it a brand new appearance with no risk of damage.  Try asking local sand blasters if they do vapor blasting, or know of anyone who does.   
Title: Re: Valve Cover Finish
Post by: Harry on June 22, 2023, 00:20:26
Thanks everyone.
Title: Re: Valve Cover Finish
Post by: johnk on June 22, 2023, 03:07:38
I second the motion on vapor blasting or at least glass bead blasting.
Title: Re: Valve Cover Finish
Post by: mdsalemi on June 22, 2023, 14:02:25
I believe that the "vapor blasting" still uses an abrasive media, but with a slurry. You still have the issue of abrasive media getting into places that may be difficult for it to get out of, even if the wet slurry blasting produces a finer finish. Abrasive media will do some surface alteration. Ditto for glass beading, the glass is simply another kind of abrasive.

If some kind of blasting is what you want, I'd vote for dry ice blasting which I understand is highly controllable but more importantly doesn't leave ANYTHING behind.

If you don't want to alter the surface but just clean and brighten, chemical cleaning is the way to go.
Title: Re: Valve Cover Finish
Post by: Leester on June 22, 2023, 18:50:34
I believe that Metric cleaned mine then painted it with something. It looks to have a coating of some kind as opposed to raw alloy. Could be wrong though, wouldn't be the first time.
Title: Re: Valve Cover Finish
Post by: MikeSimon on June 22, 2023, 19:12:35
I have not had mu valve cover done yet, because, for the time being, I want to preserve the remnants of the original euro emission sticker. But once I had it vapor blasted i will paint it with VHT high temp clear coat, which I usually do with all blasted aluminum engine covers.
Title: Re: Valve Cover Finish
Post by: teahead on June 22, 2023, 22:38:51
After vapor or ice blasting, get it coated (cermakoat, etc) w/a matte finish.


https://www.cerakote.com/shop/cerakote-coating (https://www.cerakote.com/shop/cerakote-coating)

(https://images.nicindustries.com/cerakote/projects/90796/harvard-radial-engine-cylinders.jpg?1685259293&size=650)