What was found
A DOOR BYPASS VALVE WAS RETURNED FOR INVESTIAGTION. THE REASON FOR RETURN WAS ON PUSHBACK, FLIGHT CREW REPORTED GREEN RESERVOIR LOW LEVEL, WHERE THE INVESTIGATION FOUND A LEAK ON THE DOOR BYPASS VALVE. THE INVESTIGATION IDENTIFIED THAT BOLT HAD SHEARED. FURTHER INVESTIAGTION AT MFG INDICATED THAT INITIATING FORCE HAD RESULTED IN A CRACK THAT PROPAGATED ACROSS THE BOLT SECTION, RESULTING IN FAILURE. THE BOLTS COULD BE YIELDED WHEN TIGHTENED. (K)