What was found
(CAN) CREW REPORTED A HYD FLUID LEAK FROM THE NR 1 ENGINE PYLON AND THE NR 1 THRUST REVERSER INOPERATIVE. MAINTENANCE DISCOVERED THE PRESSURE RETURN LINE FROM THE LT THRUST REVERSER CONTROL VALVE CRACKED. PN 271N6311-1151, IPC 29-11-51-45 -585. MAINTENANCE REPLACED THE LINE WITH A TEMPORARY FLEX LINE IAW AMM 20-10-10-01, PAGE 897 GOOD FOR 50 HOURS. THRUST REVERSER WAS THEN DEFERRED IAW MEL 78-31-01-1. 3 DAYS LATER THE FLEX LINE WAS REPLACED IAW AMM 29-01-01. SYS WAS LEAK CHECKED, THRUST REVERSER RE-ACTIVATED AND CYCLED SEVERAL TIME WITH NO FAULTS FOUND.