As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) MAG WAS RETURNED WITH A WC STATING MAG DEAD AND TEETH BROKEN. WHEN DISASSEMBLED, THE BEARING IN THE DISTRIBUTOR BLOCK WAS FOUND LOOSE. THIS CAUSED THE DISTRIBUTOR GEAR TO TILT AND CONTACT THE ELECTRODES IN THE DISTRIBUTOR BLOCK. THE BATCH CODE OF THE BLOCK WAS 0100. 12 TEETH OF THE DISTRIBUTOR GEAR WERE BROKEN IN VARIOUS LOCATIONS AROUND THE CIRCUMFERENCE OF THE GEAR. THESE PARTS WERE REPLACED, THE MAG WAS O/H AND RETURNED TO SERVICE ON ANOTHER ENGINE.