ORIGINAL: braindr
I have a GMS 1.20 it stops running when I back down on the throttle in flight. I changed the lines any Ideas?
At higher speeds the pressure from the muffler increases the fuel flow into the carb.
As you back off, that pressure remains.
If your low speed needle is too rich, the engine can shut off as the glow plug cannot overcome the cooling effect of all of the fuel.
Conversely if the mixture is too lean as you back off, the engine can stall out for lack of fuel.