What was found
IN FLIGHT FROM OMSJ TO WMKK, DURING CRUISE, NR 4 HYDRAULIC SYSTEM SUFFERED LOSS OF HYDRAULIC FLUID AND SYSTEM PRESSURE, OPERATING FLIGHT CREW ACCOMPLISHED BOEING 747-200 QUICK REFERENCE HANDBOOK PROCEDURES, AND PROCEEDED TO LAND SAFELY IN WMKK. MAINTENANCE CREW ON GROUND FOUND AND REPLACED A LEAKING CRACKED HYDRAULIC LINE LOCATED IN THE NR 4 ENGINE PYLON AND SERVICED THE NR 4 HYDRAULIC SYSTEM, IN ACCORDANCE WITH THE BOEING 747-200 AIRCRAFT MAINTENANCE MANUAL PROCEDURES, NO FURTHER LEAK NOTED AT PRESSURE CHECK. AIRCRAFT RESTORED TO NORMAL.