As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
RECEIVED ENGINE IN AFTER 32.2 HOURS SINCE MAJOR OVERHAUL. ENGINE WAS DAMAGED BY COUNTERWEIGHT FAILURE ON CRANKSHAFT. DAMAGED TO THE CRANKCASE, CYLINDERS AND ROD WAS FROM WHAT APPEARED TO BE A BROKEN COUNTERWEIGHT PIN OR FAILURE OF THE COUNTERWEIGHT BUSHING. THE BUSHING WAS FOUND IN SEVERAL PIECES. (K)