[sho305]

The disk above the filter goes on to make the incoming air go around in a circle before it drops into the filter area.

You might really have to screw with the box/cover/parts, gently bend them (when warm) if it was put together wrong before....re-train the parts to fit together again. Yes you can richen the main with a torch tip cleaner that is what I did. I removed the silencer; the part over the generator. Modding the rest of the stuff inside the box had little effect in comparison. Also run the ngk 2 plug spec'ed for the newer carts. Richen the jet just enough to run right then read the plug to fine tune mix, though my plug was always brown after that. Air cooled small engines often run a little better a little rich, also ran it in cold weather sometimes. A light tan would be ideal otherwise, on the insulator. IIRC stock is very light.