As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PILOT REPORTED AN OIL LEAK COMING FROM THE LEFT (NR 1) ENGINE AFTER FINISHING THEIR FLIGHT FOR THE DAY. MAINTENANCE INVESTIGATED THE OIL LEAK AND FOUND THE CRANKSHAFT CRACKED AROUND THE CIRCUMFERENCE OF THE PROPELLER FLANGE. WHEN MAINTENANCE STARTED TO REMOVE THE PROPELLER THEY FOUND AN O-RING IN-BETWEEN THE PROPELLER HUB AND THE CRANKSHAFT FLANGE, WHICH WAS NOT SUPPOSED TO BE THERE. THIS MAY OR MAY NOT HAVE CONTRIBUTED TO THE FAILURE.