What was found
DURING CLIMB AT APPROX FL 250 FELT 2 PRONOUNCED THUMPS THEN CONTINUOUS VIBRATION. 1ST AND 2ND OFFICER OBSERVED FLUID VENTING FROM RIGHT WING. LOST APPROX 1200 OF FUEL FROM TANK 2A. RAN ABNORMAL PROC. RETURNED JFK. NO ABNORMAL ENGINE INDICATIONS. FOUND EVIDENCE OF FUEL AT RIGHT WING VENT & LOWER SURFACE OF AILERON. UPON INSP OF VENT LINE IN TANK 2A, FOUND LINE IN OUT BOARD SECTION LOOSE. R & R DAMAGED SEALS AT THREE CONNECTIONS AS PER MM 28-00-00. VENT LINE NOW SECURE. REFUELED TANK. NO LEAKS NOTED. ALSO INSPECTED EXTERIOR OF A/C WITH SLATS & FLAPS EXTENDED. NO DEFECTS NOTED.