As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ENGINE WAS SENT FOR REPAIR DUE TO GENERATING METAL. UPON DISASSEMBLY FOUND THAT THE SHAFT ON THE FORWARD SIDE OF THE CENTRIFUGAL BREATHER GEAR WAS FRACTURED IN THE AREA OF THE RADIUS WHERE THE SHAFT JOINS THE GEAR. THE RELATIVE MOTION BETWEEN THE SHAFT AND THE GEAR WAS THE CAUSE OF METAL GENERATION.