As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHILE IN THE PROCESS OF REMOVING AND REPLACING A ENGINE OIL TEMP PROBE, MECHANIC DISCOVERED ONE OF THE ENGINE CASE THROUGH BOLTS WAS MISSING NUTS AND WASHERS ON BOTH SIDES OF THE CASE. THE WASHER FOR THE RT SIDE OF THE BOLT WAS FOUND IN THE BOTTOM OF THE COWLING. THE OTHER WASHER AND TWO NUTS WERE NOT FOUND.