What was found
DIVERTED TO ORD DUE TO THE LOSS OF APU OIL QUANTITY. OIL LEAK CONFIRMED IN TEST CELL AT 12:00 WHEN GEARBOX PRESSURIZED (SIMULATES APU OPERATION IN ALTITUDE). STAT-O-SEALS AT THE 12:00 POSITION, BETWEEN THE GEARBOX AND DRIVEN COMPRESSOR WERE LEAKING IN THE THE BLEED AIR DUCT. REBUILT COMPRESSOR MODULE AND ALL SHIMMING CORRECTED. THREE WASHERS INDICATE LIMITED SEAL DEFORMATION. TEST CELL LEAK CHECK AND BUILD PROCEDURES ARE BEING CHANGED TO ADD A LEAK CHECK WITH GEARBOX PRESSURIZED AT IDLE CONDITIONS, AND A LEAD CHECK ON THE BOLT TORQUES.