What was found
AIRCRAFT DEPARTED. SHORTLY AFTER TAKEOFF, NR 2 ENGINE OIL PRESSURE FELL BELOW 25 PSII. ENGINE SHUT DOWN. UPON INVESTIGATION, FOUND O-RING ON OIL TRANSFER TUBE BETWEEN GEARBOX AND OIL/FUEL HEATER DAMAGED. REPLACED O-RING, SERVICED ENGINE OIL, OPS AND LEAK CHECKED GOOD. RETURNED TO SERVICE.