As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(AUS) ENGINE OIL SYSTEM CHECK VALVE O' RING JAMMED CHECK VALVE IN OPEN POSITION. SB3178R2 DELETES THE O' RING FROM THE CHECK VALVE. PERSONNEL/MAINTENANCE ERROR. ENGINE SERIAL NUMBER PCE-93183. SEEALSO MDR 03/0629 FOR SIMILAR DEFECT ON OTHER ENGINE OF SAME AIRCRAFT.