I retired from making Scag.I would call R&D or Customer Service at the factory.Scag is made by MOM(Metal craft of Mayville) in Mayville Wi. 8 miles away they make the John Deere(Horicon Wi)
Had it checked by another BYM and he said coil was good and checked the switch and still no spark.If coil is good and unhook switch there has to be spark.