As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ACCOMPLISHED AIR TURNBACK DUE TO LOSS OF ALL OIL IN ENGINE NR 1, DURING CLIMBOUT. FOLLOWED SHORTLY BY A DROP IN OIL PRESSURE INTO THE MID TO LOWER AMBER BAND. FOUND NR 1 ENGINE HYD PUMP SHAFT SEAL CAVITY LEAKING OIL DURING IDLE RUN. HYD (EDP) PUMP SHAFT SEAL FOUND TO BE DAMAGED. REPLACED PER MM 29-11-05. NR 1 ENGINE SERVICED WITH 10 QTS.