That year cub most likely has a 23hp Kohler engine on it. If you didn't hear a bunch of grinding going on the the flywheel magnets probably haven't fallen off yet. On me side of the blower cover there should be a voltage regulator. It is screwed into the plastic cover and should have a silver ground strap that ties the regulator to metal for a ground. The screw loosens up and no longer provides a ground so the regulator doesn't work. I bet if you take care of that it will charge again
