964 3.6L WOT Switch Piece ID help & Paint on INSIDE of valve covers?

Tom '74 911 · 03-07-2011, 02:08 PM

Hello -

Sorry for the cross post - I posted this in the 911 forum as well as I am more familiar w/the traffic there vs here.

I spent the weekend rubbing my fingers raw while cleaning my (new to me) '90 964 3.6L engine. Being more familiar w/CIS and my old 2.7L engine, I'm using the PET diagrams to learn what everything is as I go along.

Firstly, there is what looks to be flaking paint on the INSIDE of the valve covers. This can't be good. I talked to my "guy" and also did a search and can't believe it's true. . . Is this really factory? What's the path of least resistance to solving this issue? Media blasting? Spending (another, gulp) $600 on aftermarket valve covers?

Also, I found this broken piece on the right side of the injection which I think operates the WOT switch? I can't find it in the PET diagrams. It is located on the right side of the injection, opposite the main throttle lever on the left side and the shaft that the piece goes on rotates directly w/the throttle. Also, it was missing a circle clip or any retaining mechanism - is this correct?

Can someone help me ID this little plastic piece?

Thanks,
Tom

porterdog · 09-09-2011, 07:26 AM

I know, I know... old thread. But! I'm in the same boat wrt the WOT cam and wanted to answer the question for posterity.

1. Yes, the indicated cracked part is the WOT cam. There's a good thread on Rennlist.

2. Yeah, paint on the inside of the valve covers. WTH. I blasted and powdercoated mine; we'll see how it holds up. FWIW, it was a real biatch to get the old coating to come all the way off; it took hours in the blast cabinet.

AOW162435 · 09-09-2011, 06:16 PM

Quote:

Originally Posted by porterdog

2. Yeah, paint on the inside of the valve covers. WTH. I blasted and powdercoated mine; we'll see how it holds up. FWIW, it was a real biatch to get the old coating to come all the way off; it took hours in the blast cabinet.

Why not just strip the covers completely (bead blast), and then get just the outside powder coated? The inside of the covers will always have a layer of oil - just like the inside of the engine case.

Andreas

porterdog · 09-09-2011, 09:53 PM

There are areas not exposed to oil on the backsides, especially the uppers. Raw magnesium corrodes pretty badly so some coating is required.

The factory coating was actually pretty elaborate- there was a heavy primer layer with some type harder cover-coat over the top.

If the powder coat gets compromised I'd probably just buy a set of CNC'd replacements.