What was found
(CAN) ACFT JUST CAME OUT OF INSPECTION. IT HAD ALL HYDRAULIC LINES REPLACED FOR 6 YEAR REPLACEMENT. ACFT WAS GROUND RUN AND LEAK CHECKED SERVICEABLE. ACFT DEPARTED A DAY LATER, AFTER ARRIVING PILOT DID A POST FLIGHT INSPECTION AND FOUND HYDRAULIC FLUID LEAKING FROM A LINE. THE MECHANIC DROVE TO DESTINATION INSTALLED ANOTHER NEW LINE. ACFT RETURNED TO SERVICE. AFTER INSPECTING AND LEAK TESTING LINE FOUND 2 PIN HOLES IN LINE. WE HAVE HAD 3 FAILURES OF THIS SAME LINE ON 3 SEPARATE MACHINES. ALL 3 LINE HAD LESS THEN 5 HRS FROM BRAND NEW RIGHT FROM MFG.