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 SPLINE ADAPTER INNER SPLINES. INSTALLED NEW ADAPTER. SEE MMIR# 4305 FOR SPUR ADAPTER GEARSHAFT WHICH WAS ALSO REPLACED.