Bad transition on Brisson 3.2?
John,
If not the fuel or gaskets, I would look at my ignition battery circuit. I've had the same problem on a Brison 2.4 caused by a low/faulty ignition battery - voltage was good (5.1volts), but amperage output was only about 100ma. Also the switch can cause problems after a year of running - gunk in the switch causing faulty contact, or just plain worn down contacts from vibration.
After that, I would check out the spark plug. Is this on the Stinger?