[cabmandone]

Got an engine diagram? You mention magnets on the flywheel so I'm assuming you have an ignition coil. Have you verified that the gap is right between the coil and the flywheel? Could be something as simple as a thumb kill switch on the grip. I overlooked that on a 4 stroke 4 wheeler I had. I struggled to get spark and then had a "well duh!" moment.

From looking at a manual I found online, there is a lift lever that appears to be a kill switch possibly? I know yours isn't running at all but might this be why?
Problem 10: Engine Continues To Operate When Lift Lever
Is In Rear Position
A. A wire connection is disconnected from the engine
terminal block.
B. The wire is disconnecteq from the ground switch.
C. The engine surface is covered with debris where the
ground switch contacts the engine.
For engine related problems refer to McCulloch Engine
Owner's Manual.