As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) PILOT REPORTED LOUD BANG IN FLIGHT. DISCOVERED ALTERNATOR BOLT SLIPPED OFF PULLEY AND REMAINED INTACT WRAPPED AROUND PROP SHAFT. ALSO NOTICED CONSIDERABLE OIL SEEPING FROM OIL PUMP INTAKE HOSE AT ITS CONNECTOR. UPON CHECKING SECURITY OF HOSE, IT BROKE APART IN HAND.