As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER INSTALLATION OF RT ENGINE, WHILE PERFORMING ENGINE FUEL SET-UP AND ADJUSTMENT OF MANIFOLD PRESSURE, THERE WAS A DECREASE IN MANIFOLD PRESSURE AND A NOTICEABLE NOISE AND VIBRATION FROM THE RT ENGINE. UPON FURTHER INVESTIGATION IT WAS NOTED THAT THE TURBOCHARGER MAIN BEARING SEAL HAD FAILED CAUSING BEARING FAILURE.