As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) ON CLIMB OUT #3 ENGINE FIRE WARNING WAS ACTIVATED. EMERGENCY PROCEDURES WERE CARRIED OUT AND AIRCRAFT RETURNED TO POINT OF DEPARTURE. INSPECTION FOUND THE 13TH STAGE SUPPLY MANIFOLD BLOWN, WHICH DAMAGED THE UPPER COWLING. SUPPLY MANIFOLD REPLACED AND COWLING INSPECTED AND REPLACED.