As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING SCHEDULED ENGINE INSPECTION, CRANKSHAFT LOCK TAB WAS FOUND IN THE OIL SUMP SCREEN. REMOVED SUMP AND ACCESSORY HOUSING TO VERIFY. TAB ON BOLT WAS CONFIRMED BROKEN. CRANKSHAFT GEAR BOLT WAS FOUND TO HAVE MINIMAL TORQUE REMAINING. (LESS THAN 100 INCH/POUND). NEW BOLT AND LOCKPLATE INSTALLED PER LYCOMING INSTRUCTIONS AND RE-ASSEMBLED ENGINE. ENGINE HAS 295.6 HOURS SINCE FACTORY OVERHAUL ON 10-21-97.