What was found
DFW - FLT 123 - AT ROTATIO DURING T/O, FIRE WARN AND RT HYD TEMP HIGHT LIGHTS ILLUMINATED FOR NR 3 ENG. ACCOMPLISHED SHUTDOWN OF NR 3 ENG AND FIRE WARNING LIGHT EXTINGUISHED. A/C DUMPED FUEL AND RETURNED TO DFW, LANDING WITHOUT INCIDENT. REPLACED NR 3 ENG. ACCOMPLISHED LEAK AND GROUND CHECKS WITH NO DEFECTS FOUND. A LOOSE CLAMP ON A STARTER DUCT JOINT LED TO JOINT FAILURE RESULTING IN HIGH UNDER COWL TEMP AND A FIRE WARNING. SUBSEQUENT FAN CASE ABRADABLE SHROUD MATERIAL DISBONDING OCCURED DUE TO IMPINGING HOT AIR FROM THE FAILED STARTER DUCT JOINT. ENGINE PROCESSED THROUGH SHOP FOR RETURN TO SERVICE. (M)