As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ENGINE REMOVED DUE TO TURBINE OVERHAUL. UPON INSPECTION OF COMPRESSOR PARTS NOTED THE FOLLOWING: STEP WEAR BEYOND LIMITS ON SPUR ADAPTER GEARSHAFT FORWARD AND AFT SPLINES. INSTALLED NEW SPUR ADAPTER GEARSHAFT. SEE MMIR# 4306 FOR ADAPTER WHICH WAS ALSO REPLACED.