What was found
UPON LT ENGINE START-UP THE OIL PRESSURE WAS BELOW LIMITS AT 1000 RPM. WHILE TROUBLESHOOTING LOW OIL PRESSURE, WE FOUND FOREIGN MATERIAL UNDER OIL PRESSURE ADJUST SEAT. INVESTIGATING IT, FOUND THE LT MAGNETO HAD MOVED (ROTATED) POSITION. UPON REMOVAL OF LT MAGNETO THE IMPULSE COUPLING WAS FOUND DESTROYED. THE IMPULSE SHELL WAS GONE (HAD FALLEN INTO THE ENGINE). RETAINING NUT, WASHER AND COTTER KEY WERE STILL INTACT. IT IS HARD TO DETERMINE WHAT THE ACTUAL FAILURE WAS. WE BELIEVE 1 OF THE PAWLS MAY HAVE COME LOOSE. THE PAWL ATTACH RIVET WAS STILL IN PLACE. THE MAGNETO DRIVE RETAINER AND BUSHINGS WERE ALSO DESTROYED WITH MOST OF THE PIECES HAVE FALLEN INTO THE ENGINE. MAGNETO AND ENGINE WILL BE SENT FOR ANALYTICAL INSPECTION.