As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING RUN UP THE PILOT EXPERIENCED ABNORMAL RPM DROPS WHEN CHECKING THE MAGNETOS. THE MAGNETO MODEL NR 4371 SERIAL NR 18021142 TIMING TO THE ENGINE WAS FOUND TO BE 20 DEGREES BTDC INSTEAD OF 25 DEGREES BTDC. UPON OPENING THE COVER OF THE MAGNETO THE ROTOR AND M-3485 BEARING CAP ASSEMBLY WERE FOUND LOOSE. THE POINTS CAM WAS FOUND TO HAVE NO LUBRICATION. INTERNAL TIMING WAS FOUND GROSSLY OUT OF SPECIFICATION.