What was found
FLT 467, BOS-RSW, AT 29000 FT CABIN WENT THRU 9000 OUTFLOW WAS AT FULL CLOSED POSITION. COULD NOT STOP CABIN FROM CLIMBING. DESCENDED TO 24,000 FT, CABIN STABILIZED AT 6900 FT. DIVERTED TO JFK. FOUND PRESS LEAK FROM NR 2 PACK OUTLET BELLOWS. REMOVED AND REPLACED OUTLET PACK BELLOWS PER AMM 21-51-21. OPS CHECK & LEAK GOOD PER AMM 21-31-00-720-802A. OK FOR SERVICE.