Time to fess up........ Copper washer slipped off of valve and disappeared.
I took several valve parts out to try to retrieve washer, along with side
plate hoping to find it. It is still in there somewhere. I reassembled everything and tried to start it thinking it might fall through to bottom of IP. I was amazed when it started up, but it ran poorly and won't shut down unless I put in gear and popped the clutch.

Is there any way to access IP valve body and shut down assembly without pulling IP? Is it possible that IP may still be saved?