Well I just got back from the lawn/garden place in town. They had the screen I lost and I asked them about the problem. They looked it all over and said it felt like the little flappers (I don't know the exact term for the components carbs. aren't my best subject) on the fuel inlet side seemed pretty stiff. They swapped out all the gaskets and related gear for new parts. Hopefully I'll get a chance to fire the engine up this week.

BobH,

Before I figured out that richening up the low end needle would sometimes solve the problem, I just flew it that way (first gasser, assumed it wasn't too big a deal). Then I had a dead stick and broke a set of carbon gear in the weeds so I started trying to locate the reason. When the engine has the issue it's from the time I start it. It's not like it's OK and then a few minutes later decides to act up. If I start it and it's working right, it stays that way. If I start it and it won't transition, it stays that way until I fiddle with the needle.

The guy at the mower shop seemed to know more than me (about that carb. anyway) so I'll assume the internals are correct. I'll fire it up hopefully tonight/tomorrow.

Ben