AN MD90; ON A TEST FLT FOR CHRONIC R ENG COMPRESSOR STALLING; REJECTED TKOF DUE TO R ENG STALL. FOUND CHK VALVE NOT INSTALLED ON ENG PNEUMATIC PACKAGE.

Narrative

DURING THE PERIOD IN SEP/03; ACFT EXPERIENCED SEVERAL INCIDENTS OF STALLING DURING DSCNT. AFTER EACH INCIDENT; NUMEROUS INSPECTIONS WERE PERFORMED; AND PARTS WERE REPLACED PER TROUBLESHOOTING CHARTS. AFTER A MULTIPLE-PART REPLACEMENT AND INSPECTION WAS PERFORMED ON SEP/MON/03; THE ACFT WAS SET UP FOR A VERIFICATION FLT ON SEP/TUE/03. IT EXPERIENCED A REJECTED TKOF DUE TO #2 ENG STALL. IT WAS SUBSEQUENTLY DETERMINED THAT THE #7 CHK VALVE WAS NOT INSTALLED ON THE #2 ENG. RECORDS SHOW THE ENG WAS RECENTLY INSTALLED. ENG WAS CONVERTED FROM A #1 TO A #2 ENG PRIOR TO BEING INSTALLED. DURING ENG CHANGE BUILD-UP; MULTIPLE EMPLOYEE SHIFTS CONTRIBUTED TO ENG CONVERSION. WHEN ENG WAS COMPLETED; STEP 14 OF ENG BUILD-UP SHEET REMAINED BLANK. THIS STEP INVOLVES INSTALLING THE PNEUMATICS PACKAGE ON THE ENG; BUT NOT RIGGING IT; UNTIL THE ENG IS ON THE PYLON. ONCE THE PNEUMATICS PACKAGE IS INSTALLED; THE VALVE CANNOT BE SEEN; ONLY A SMALL TAB PROTRUDES; INDICATING VALVE INSTALLATION. SINCE THE PNEUMATICS PACKAGE WAS ALREADY IN PLACE; I CHKED THE INSTALLATION FOR CORRECT HARDWARE CLAMPS; AS WELL AS VALVE INSTALLATION; AND SIGNED STEP 14 OF THE BUILD-UP SHEET. WHAT CAN BE DONE TO PREVENT A RECURRENCE OF THIS PROB IS TO ENSURE ENG IS LEFT INTACT AFTER INSPECTION AND PRIOR TO INSTALLATION. SECONDLY; ENSURE ANY 'ROBBED' PARTS ARE DOCUMENTED ON PARTS SHORTAGE SHEET. THIRD; REQUIRE A THOROUGH 'PRE-INSTALLATION INSPECTION.'