I have a 140hp Tohatsu Outboard the motor is turning very slowly when trying to start it. The battery is fully charged. If I take the spark plugs out of the the motor it turns very fast, however when I replace the spark plugs the motor drags or turns very slowly when trying to start it. I had previously had water in my fuel, but since changed the water separater filter and the in-line fuel filter. Any ideras on what would cause the motor to drag or turn slowly with the plug in?\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\