What was found
ON TAKEOFF, T-5 WAS IN THE YELLOW AND 51 DEGREES HOTTER THAN THE NR 2 ENGINE, RETURNED TO DEPARTURE AND DID POWER CHECK AND THE NR 1 ENGINE FAILED CHECK. MAINTENANCE REMOVED NR 1 ENGINE ASSY, SN 2055TEC, AND INSTALLED SERVICEABLE ENGINE ASSY SN 20537TEC. (SW03200410323)