As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PILOT FLEW A/C IN FOR GENERATOR REPAIR AND REPORTED TO MAINT THAT THE ENGINE WAS MAKING A CLUNKING NOISE. UPON FURTHER INVESTIGATION WITH A BORESCOPE THE CRANK SHAFT WAS FOUND TO BE BROKE AT APPROX. THE NR 6 PISTON CONNECTING ROD JOURNAL. ENGINE HAS NOT YET BEEN DISASSEMBLED FOR FURTHER FINDINGS.(K)