What was found
FOUND NR 2 ENGINE COMBUSTION DRAIN VALVE WAS NOT WORKING, REMOVED DRAIN FOR REPLACEMENT AND FOUND A PIECE OF METAL WEDGED INTO COMBUSTION DRAIN VALVE. METAL PIECE REMOVED FROM THE DRAIN VALVE IS APPROX. 0.278 L X 0.272 W X .028 THICK WITH 3 BROKEN EDGES AND 1 MACHINE FINISHED EDGE. AFTER CONSULTING WITH A MANUFACTURER, A SPECIFIC DETERMINATION OF WERE THE PIECE OF METAL CAME FROM CANNOT BE MADE UNTIL THE ENGINE IS TORN DOWN. THE POWER CHECKS OF THIS ENGINE HAVE BEEN DECREASING IN MARGIN FOR THE LAST 130 FLIGHT HOURS, THERE HAVE BEEN NO INDICATIONS OF ANY EMINATE FAILURES.