As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
UPON INSPECTION OF GEARBOX PARTS DURING DISASSEMBLY, FOUND CUT O-RING UNDER SCREEN NR 6840136 IN OIL DELIVERY TUBE OIL PASSAGE. THIS COULD HAVE CAUSED RESTRICTED OIL FLOW TO OIL DELIVERY TAKE WHICH LUBES 2-1/2 BEARING AREA. SUBMITTER STATED LACK OF OIL IN 2-1/2 BEARING WAS POSSIBLY CAUSE FOR 2-1/2 BEARING BREAK-UP.