I Have A 1987 Mariner 40 HP (Jap Model) 2 Cyl<br />After 20 To 30 Minutes Of WOT It Starts To Foul Plugs One At A Time. I Have Tried Different Brands And Different Heat Ranges I Am Currently Using Champion Plugs.<br />I Have Checked Compression And Spark And They Check Ok. I Changed Fuel Tank...
