Small Engines (Lawn Mowers, etc.): 14HP V-Twin Briggs plugs fouling out, briggs and stratton, plug gap

Question
My 14 HP V- Twin Briggs and Stratton engine runs great for approx 5-10 when I clean the plugs, then it fouls the plugs out. Any suggestions???

Answer
Could be a couple of things. The needle valve could be sticking inside causing it to flood somewhat, and run rich (too much fuel). And fuel fouling. Might be getting old, and oil is passing by the rings, and the plug is oil fouling. I have also seen a magneto producing a weak spark, clean plugs help it fire enough for a little while, then it fouls out. Also check, and make sure your plug gap is correct, and that they are the correct plugs for that engine, a wrong set of plugs could be running to cold to clean themselves........Tom