What was found
AIRCRAFT UNABLE TO MAINTAIN NORMAL CABIN PRESSURE CLIMBING. CREW SELECTED RT RECIRC OFF TO FORCE PACKS TO HIGH FLOW. OUTFLOW VALVE FULL CLOSED TO MAINTAIN CABIN PRESS. AT FL360, CAB ALT AND DP IN NORMAL RANGE. DETECTED EXCESSIVE CABIN PRESS LEAKAGE. FOUND LEFT PACK REVERSER FLOW CHECK VALVE LEAKING AT BOOT, DUE TO CLAMP NOT INSTALLED PROPERLY AND HOT AIR TRANSFER TUBES LEAKING. REPLACED TUBES AND BLEED AIR VALVE, ALSO FOUND AFT CARGO DOOR SEAL LEAKING.