Manley, I've been experiencing similar problems with one of the new 3W150b2ss engines. I have a TOC'd 140 that I REALLY love, though. It's the most dependable 3W I have. BUT. . as to your problem. . it sounds like fuel is puddling inside the crankcase, just above the reed valve assembly, and then when you roll inverted it falls into the engine, effectively flooding it and probably killing it. Your symptom of it blowing smoke and gurgling/running badly upon acceleration for takeoff tends to support this. I do not know if you NEED it this rich (two turns out on the low end), just to get it started, but if you do it's indicative of a warped phenolic carb mounting block.

If the engine will start at a leaner low-end mixture adjustment, I'd advise setting it that way, since your symptoms are of an overly-rich bottom end on the carburetor. If, however, it NEEDS to be this rich to run properly, take the carb block off, flatten it with some sandpaper, reseal it with some 3M "yellow weatherstrip adhesive" available at any automotive parts store, and reset the needles once you have the engine running again. The yellow adhesive is tenacious and pervasive, adn we in the automotive busines nicknamed it "Yellow Death" since you will probably die before it comes off your skin.

Really, about 3/4-1 turn on the bottom and 1.25-1.5 on the high end is the "normal" adjustment range for the needles on your carburetor. Anything outside that range, especially richer, would support your having an airleak under the carburetor.

Hope this helps.