As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PRIMARY COIN HOLD DOWN RETAINERS LOOSE WITHIN MAGNETO CASE. THE LOOSE RETAINERS, IN TURN, GOT CAUGHT IN THE TIMING WHEEL/GEAR AND CHEWED UP SEVERAL TEETH. PROBABLE CAUSE- THE RETAINERS WERE NOT INSTALLED PROPERLY. FORTUNATELY THE DAMAGE WAS AT THE R20 TIMING MARK, WHERE WE WERE ABLE TO SEE THE DAMAGE DURING A 10 HOUR (ENGINE BREAK IN) VISUAL INSPECTION.