As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SLICK MAGNETO LOCKED UP AND CLIPPED A GEAR TOOTH AND METAL SHAVING. THIS WAS DURING A TRAINING FLIGHT AND OCCURRED JUST AS STUDENT WAS LANDING AS HE HEARD A LOUD NOISE EMITTING FROM THE ENGINE COMPARTMENT. ON TEAR DOWN. FOUND THAT THE MAGNETO WAS LOCKED, AND ONE GEAR TOOTH WAS CLIPPED, AND METAL FILING WERE FOUND IN THE AREA.