As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING ANNUAL INSPECTION FOUND KNURLED NUT WORN BEYOND LIMITS. UPON REMOVAL OF THE KNURLED NUT AND TAIL ROTOR BALANCE WHEEL FOUND THREADS ON TAIL ROTOR GEARBOX OUTPUT SHAFT, UNDER BALANCE WHEEL, EXCESSIVELY WORN AND GALLED. CUSTOMERS PILOT REPORTED THAT THEY HAD EXPERIENCED DIFFICULTY IN MAINTAINING TORQUE ON THE KNURLED NUT.