As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THIS VALVE WAS WORKING PROPERLY WHEN REMOVED FOR SB 550-21-41. FURTHER INSPECTION FOUND CRACK IN POPPET AREA. IF IT HAD CRACKED MORE, IT IS POSSIBLE THAT THE CABIN WOULD HAVE DEPRESSURIZED. SUBMITTER STATES IF THIS SB APPLIES TO AIRCRAFT, C/W AS SOON AS POSSIBLE OR HAVE FREQUENT INSPECTIONS UNTIL ACCOMPLISHMENT. THIS IS ALSO AIRESEARCH BULLETIN 103576-21-4056.