I have a 30hp Evinrude that is fouling the plug in the #2 cylinder and the fouling is molten aluminum that is from the piston. My experience is that a lean condition is the cause, but I am confounded by its presence in only one cylinder. I was advised to first check the plugs to assure they were the proper heat range and then to be certain the timing was set correctly. The timing is set to 30 degrees under load at full advance. Any ideas?