Hello, have you looked at the flywheel key it could be sheared? also
have you checked the gap between the flywheel and coil? I would guess
this mower is a electronic ignition model so no points it could be the
ignition module on the coil, you said you checked the wiring so i would
guess you have power to the positive side of the coil? if this doesn't
work than i would replace the module if this is old enough it does have
points i would make sure they are working and have the coil checked. I
have seen the ignition switch go bad and no power to the coil.