What was found
GUA - FLT 503 - AFTER PASSING 1,000 FEET AGL, A COMPRESSOR STALL WAS HEARD, ENG NR 3 PARAMETERS BEGAN TO FLUCTUATE. EGT EXCEEDED THE TAKEOFF LIMIT THROTTLE, NR 3 WAS REDUCED. EVEN THOUGH, ENGINE CONTINUED TO VIBRATE WITH THE ENGINE VIBRATION CAUTION LIGHT ILLUMINATED. AT THIS POINT, ENGINE WAS UNCONTROLLABLE. ENGINE FAILURE AND SHUT-DOWN PROCEDURE WAS PERFORMED, IT WAS INSPECTED. FOUND SMALL METAL PARTICLES IN EXHAUST AREA. CHANGED ENGINE NR 3, TESTED IAW MM 71-00-00. OK. ENGINE S/N ON: LF07323, OFF: LF07314. HOURS, 3,171. CYCLES, 2,868.