As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING '1C1' CHECK, LEFT ENGINE CHANGE FOUND THE FORWARD ENGINE MOUNT FORWARD ATTACH NUTS CRACKED. FURTHER INVESTIGATION REVEALED THAT IMPROPER CONFIGURATION NUTS WERE PREVIOUSLY INSTALLED (P/N LH7461T144D) PROPER CONFIGURATION IS (VN401B144). REPLACED ENGINE (P/N CMF56-5), (S/N 731569; 11692 T50) AND ASSOCIATED MOUNTING HARDWARE.