As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
MAGNETO DRIVE GEAR WAS SEIZED TO CRANKCASE BUSHING WHICH WAS SPINNING IN ITS CRANKCASE BORE. THIS ENGINE HAD ONLY 219 HOURS SINCE FACTORY REMANUFACTURE. THE OPPOSITE ENGINE WHICH ALSO HAD 219 HOURS SINCE FACTORY REMANUFACTURE EXHIBITED THE EXACT SAME PROBLEM. BOTH ENGINES WERE REMOVED AND SENT OUT FOR REPAIR.