I've got a ryobi 31cc engine mounted on an ultra easy stick. No cowl. The problem I'm having is the engine flames out after about 30 seconds of vertical at full throttle (actually anything above idle). Otherwise it runs perfectly.
I'm using a zinger 18-8 prop and 11mm walbro carb.
The end of my fuel tank is about 12" from the front of the carb, have 5/8" clearance carb to firewall, and have good tank venting.
I've tried running a little rich on the high end to where it occasionally 4 cyles, and reversed my pump cover to reposition the vent, but these didn't seem to make a difference.
I'd like to get this figured out because this setup at 12.5 lb hovers easily, but I have to do it high up in case the engine quits. Any ideas?