At close to or full throttle, for extended time (maybe 8 to 10 minutes), the temperature guage slowly drops to cold and the alarm buzzer sounds.Buzzard stops after returning to idle speed or turning engine off for a couple of minutes.Manual says buzzard will sound if engine is over heating not when cold. Why would temperature drop at high speeds, anyways?Does motor have a thermostat? Maybe it is stuck open, therefore temperature drop at high speed?? But why nthe buzzard?Thanks,Tom