As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER APPROX 3 HRS OF FLT WHILE CRUISING AT FL 330 NO 1 HYD SYSTEM QTY SLOWLY DECREASED FROM 6.0 GALS TO 2.8 GALS AND STILL SLOWLY DECREASING. TURNED OFF #1 HYD PUMPS C/W RED TABS. TURNED PUMPS ON FOR LANDING, CONFIGURATION TO FLAP 35 EXTENSION NOTED 2.3 GALS ON FINAL APPROACH. REPLACED HYD LINE ASSY PER M.M.20-10-01-2, TYPE 2 REPAIR. SERVICED #1 HYD SYSTEM AND OP'S AND LEAK CHECKED NO LEAKS NOTED A/C OK FOR SERVICE.