What was found
DURING CLIMB TO 38,000 FT TO FLIGHT LEVEL OF 40,000 FT, THE CABIN STARTED TO CLIMB 2000 FT PER MINUTE. CAPTAIN DECLARED AN EMERGENCY AND DESCENDED TO A SAFE OXYGEN LEVEL AND LANDED. TROUBLESHOOTING THE SYS FOUND NUT, PN MS210433 HAD SEPARATED FROM COUPLING, PN 744210-4 ON COALESCER BAG HOUSING PN 750346-2, THIS CAUSED THE CABIN PRESSURE SYSTEM TO FAIL. INSTALLED A NEW NUT ON THE COUPLING AND THE SYSTEM IS NOW FUNCTIONING NORMAL. THE MM ONLY CALLED FOR 20-25 INCHES OF TORQUE, NOT ENOUGH. ALSO, MM DOES NOT REQUIRE COUPLING TO BE SECURED WITH SAFETY WIRE.