I just cant be sure about the valve, so I'm pulling it off the third line and replacing it with a j-tec fill nozzle and plug. It's simple and then I can be sure I don't have a pressure leak on the third line.

Just when debugging the new airplane was plenty interesting, another variable has surfaced. When I took the cowl off, I noticed some pink dust on the engine. Upon inspecting the cowl, a bare spot where the red paint had been ground away is telling me that part of the shaft is rubbing against the cowl! That would rob 1000 RPM or so, no?

I just cant imagine how this is happening, however, as the cowl looks perfectly centered on the prop plate with 1/4" clearance all around, but the evidence is irrefutable. Maybe vibration? I just don't know how I can center it any better???