My neighbor asked me to look at their Cub Cadet with a Kawasaki engine, she said her husband hit something and it stopped running and wouldn't restart. The shaft doesn't appear to be bent but it will need a new blade. My first thought was a sheared flywheel key but it's fine. I hate to spend $75 on a coil when I know this machine was working fine until it hit something. What could I look for that could be the culprit here.