17hp Kohler timing

I have a 1990 Cub Cadet 1730 lawn tractor with the Magnum 17hp Kohler. It started having problems starting so after checking for ignition spark, and found none, I installed a new ignition module along with new plugs. It now has spark as I check with a plug out and grounded to the head, but will not fire at all. Along with the new ignition module, it has a new fuel pump, carb kit. Also have the ground wire disconnected from the module to insure that the module wouldn't be grounded to the the ignition key.Either way it doesn't fire. Is there any way the timing can get off on one of these. The key on the flywheel is ok. Any ideas or advice would be appreciated.