What was found
DURING CRUISE, FL380, THE LEFT ENGINE OIL INDICATED ZERO, FOLLOWED BY LOW OIL PRESSURE. CONDUCTED A PRECAUTIONARY SHUTDOWN OF THE ENGINE IAW QRH. SINGLE ENGINE TIME WAS 42 MINUTES. AN EMERGENCY WAS DECLARED, THE AIRCRAFT WAS GROUNDED. REPLACED THE STARTER VALVE IAW AMM 80-11-03-402, REPLACED THE STARTER, AND STARTER SHAFT IAW AMM 80-11-01-400, ACCOMPLISHED AMM 71-00-00-210-802-F00, REPLACED THE NR 1 ENGINE STARTER QUADRING ADAPTER AND CHECKED FOR DEBRIS IAW MM 80-11-02-400. ACCOMPLISHED ALL STEPS OF MIC 70357514. LEAK CHECKED AND ENGINE TESTS CHECKED SATISFACTORY.