What was found
(CAN) DURING MAINTENANCE GROUND RUN IAW MM-1-5/27, THE ENGINE FLAMED OUT WHEN THE BOOST PUMPS WERE SHUT OFF. THIS FAILURE WAS REPEATABLE. TROUBLE SHOOTING REVEALED AIR ENTERING THE FUEL SYSTEM THROUGH THE AIRFRAME FUEL FILTER ASSEMBLY DRAIN VALVE. THE AIRFRAME FUEL FILTER ASSEMBLY P/N 222-366-621-001 WAS REPLACED WITH P/N 222-366-621-003 AND THE AIRCRAFT WAS RUN IAW MM-1-5/27. THE PROBLEM WAS RECTIFIED. THE DEFECTIVE PART TRACEABILITY IS BEING REVIEWED.