As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHILE INVESTIGATING OIL LEAK FROM TURBO, FOUND IMPELLER/TURBINE SHAFT HOLD DOWN NUT LOOSE ALLOWING SHAFT TO MOVE LATERALLY. THIS CAUSED SHAFT TO BECOME UNSEATED AT BEARING SEALS. DISCREPANCY WAS DISCOVERED EARLY ENOUGH TO KEEP IMPELLER AND TURBINE WHEELS FROM BEING DAMAGED. NOTE: TURBO WAS REPAIRED 1.9 HRS EARLIER. TURBO WAS REPAIRED AND INSTALLED. (K)