I installed the new "o" ring awhile back. No change. I think I'll try the K&B Needle valve since I already have one. The problem is definitely in the Needle valve. There are NO bubbles coming from the tank. There must be some other variable somewhere though because I have a second engine that adjusts out and runs fine even with the bubbles. In fact I always brag that I'll bet a paycheck It'll start on the first flip. Of course I get no takers but it ALLWAYS starts on the first flip.

We have an abundance of OS's at our field and I've only seen a problem on the 91fx's. If someone gets their plane in a tight situation and the engine carries them out we say " Thanks OS!" Kind of like the "Thanks AC" commercials that used to run on TV a while back. I guess every family has to have it's black sheep.