I have an 1863 cub with 837hrs on it with the original deck belt still on it. My father bought it new in 93 I bought it from him. I have been having intermittent spark dropage on a cylinder. It comes and goes. Well yesterday my son took a job mowing the neighbors lawn and he mowed untill dark with the intent to finish it today. We went out to start the old girl up and no spark crank all day long no spark. I've went through the interlocks and disconnected the kill at the engine harness. Still no spark. Yanked engine out of it took shroud off and I believe I found the intermittent spark issue right hand spark plug wire outer coating chewed up. But back to the problem what on the engine would cause both ignition could to not have spark? What does the regulator do? And how do I test the coils/modules there are 2. It has 2 coils 2 plugs and wires and one magnet to trigger. Like I said he mowed 2 hrs yesterday and this morning no spark. I'm ready to pull my hair out please hèlp!!!