I HAVE HAD SEVERAL PROBLEMS WITH THE SPARK PLUGS BLOWING OUT OF MOTOR AND BREAKING COIL CAUSING IT TOO LEAK FUEL VAPORS OUT POSSIBLY CAUSING A FIRE THIS HAS HAPPENED SEVERAL TIMES. THREE DIFFERENT CERTIFIED MECHANICS HAVE ADVISED THIS IS CAUSED TO DEFECT IN THE ALUMINUM HEADS FROM FACTORY NOT HAVING ENOUGH THREADS CAUSING THE SPARK PLUG TO BLOW OUT. POSSIBLY CAUSING INJURY OR FIRE. THIS ISSUE NEEDS ADDRESSED AS IT IS A SAFETY CONCERN. WE HAD A SMALL ENGINE FIRE CAUSING SLIGHT DAMAGE TO ENGINE COMPARTMENT THAT HAD TO BE REPAIRED.