What was found
WHILE CRUISING AT FL360, HEARD A LOUD POP FROM REAR OF AIRCRAFT. CABIN CLIMB INDICATOR WAS PEGGED AT MAXIMUM READING. PRESSURIZATION WAS LOST. INSPECTED J-DUCT DISCOVERED WATER SEPARATOR SLEEVE BUCK BLOWN, REMOVED J-DUCT AND INSPECTED SLEEVE, FOUND SLEEVE CUT, REPLACED SLEEVE AND INSTALLED J-DUCT. LEAK CHECK J-DUCT AND WATER SEPARATOR CHECK GOOD, ALL WORK DONE IAW HAEKER 800XP AMM 21-10-95.