What was found
2 APUS WERE REPORTED LOP AUTO SHUTDOWN. DISASSEMBLY OF THE ENGINES REVEALED LP ROLLER BEARING FAILURE. ONE OF THE ENGINE'S BEARING DID NOT HAVE LUBRICATION AT ALL. THE OIL PUMPS P/N 3880998-1 WERE ROUTED TO BENCH TEST AND LOW PERFORMANCE WAS NOTED. DISASSEMBLY OF THE OIL PUMP REVEALED PORT PLATE P/N 3603681-1 HAD SIGNIFICANTLY WORN. IT ALLOWED THE PORT PLATE MOVE TO RESTRICT THE OIL INLET PORT AND OUTLET PORT AND CAUSED LOW PUMP PERFORMANCE. THE BEARING FAILURE WAS A CONSEQUENCE OF INSUFFICIENT OIL PRESSURE.