What was found
FLT 143 JFK-PBI, AIR RETURN TO JFK DUE TO BLEED NR 2 LEAK, MSG IN FLIGHT. MSG EXTINGUISHED FOR APPROXIMATELY 2 MIN, THEN RE-APPEARED, CREW FOLLOWED QRH PROCEDURE BOTH BLEEDS OFF, MSG INTERMITTENT UNTIL LANDING. FOUND LEAK ON ENG NR 2 FWD PYLON DUCT AT CRACK WELD. REMOVED AND REPLACED DUCT IAW AMM 36-11-04. BLEED LEAK NO LONGER PRESENT AND CMC SHOWS HEALTHY ODS STATUS WITH NO FAULTS NOTED.