As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
TAKEOFF & 0:30 CREW OBSERVED LT ENG OIL QTY DECREASING ABNORMALLY. ENG WAS SHUT DOWN & ACFT RETURNED. DISCOVERED A FAILED FACE SEAL AT THE FUEL PUMP DRIVE PAD ON THE ACCESSORY GEAR BOX. A GVI OF THE SEAL WAS COMPLIED WITH PRIOR TO THE PUMP INSTALLATION THE DAY PRIOR & NO LEAKS WERE DETECTED ON THE GND RUNS FOR THE PUMP REPLACEMENT.