What was found
HYD SYS 3 ELEV OFF LT ILLUMINATED IN CRUISE AT FL 270 PERFORMED RED TAB PROCEDURES, DUMPED FUEL & RETURNED TO MEM. NR 3 HYD QUANT DROPPED TO 0. FOUND NR 3 HYD RESERVOIR LEAKING AT TOP ON INBOARD OF SIGHT EYE. SIGHT GLASS CRACKED. REMOVED AND REPLACED RELIEF AND SAMPLING VALVE, SIGHT GLASS ON RESERVOIR. SERVICED NR 3 SYSTEM HYDRAULICS. PERFORMED LEAK CK ON SYSTEM, NO LEAKS NOTED. RED TAB PROCEDURE MANUAL GEAR EXTEND HANDLE USED. RESTORED MANUAL GEAR HANDLE TO NORMAL CONFIGURATION. REMOVED AND REPLACED BOTH LT & RT NR 3 EDP'S CHECKED NR 3 HYDRAULIC MANIFOLD FILTERS, OK ALL OPS AND LEAK CHECK GOOD.