What was found
LOST OIL QUANTITY ON THE NR 1 ENGINE DURING INITIAL CLIMB. QRH PROCEDURE WAS FOLLOWED. THE OIL QUANTITY DECREASED TO ZERO.THE OIL PRESSURE DECREASED BELOW 40PSI AND THE NR 1 LOW OIL PRESSURE LIGHT ILLUMINATED. THE NR 1 ENGINE WAS SECURED FOLLOWING QRH PROCEDURES. THE ENGINE WINDMILLED FOR APPROX.3 MINUTES DURING APPROACH AND LANDING. THE OIL PRESSURE WAS NOT MONITORED DURING THE APPROACH AND LANDING. REPLACED FUEL/OIL COOLER INLET ELBOW PER AMM 79-20-001-4 AND 20-80-001-2. INSTALLED NEW SEAL ASSY AND RECONNECTED FUEL/OIL INLET TUBE PER MM 79-20-011-4. RAN NR 1 ENGINE PER JRH CH4 AND MM 72-00-00 TO 80% N2 FOR 5 MINUTES, THREE TIMES. OIL PRESSURE STEADY AT 50 PSI AND OIL QUANTITY STEADY. OIL TEMP STEADY AT 80C. OPENED COWLING AND PHYSICALLY CHECKED ENTIRE ENGINE AND OIL COOLER LINE FOR LEAKS. LEAK CHECK GOOD.