What was found
AFTER TAKEOFF, LANDING GEAR HANDLE WOULD NOT GO TO UP POSITION, ACCOMPLISHED QRH PROCEDURE. COULD NOT OVERRIDE. UPON RETURN TO GATE DISCOVERED THE RT MLG TRIM CYLINDER HYDRAULIC LINE HAS PIN HOLE. NO OTHER PROBLEMS NOTED FROM VISUAL INSPECTION. REPLACED HYDRAULIC LINE FOR RT LDG TRIM CYLINDER PER MM 32-37-03-2. BLEED HYDRAULIC SYSTEM AND LEAK CKS GOOD. ALSO, OPS CHECKED CRANK AT MAIN GEAR HYD INTER- LOCK CLYINDER AND OPS CKS GOOD. PERFORMED DUMMY GEAR SWING TO VERIFY GEAR HANDLE RELEASES AND OPS CKS NORMAL. RESAFTIED TRIM CYLINDER BYPASS LEVER TO NORMAL POSITION. A/C OK FOR SERVICE. HYDRAULIC LINE CHANGED IS REFERENCE IPC 32-37-05-01 ITEM 75.