What was found
BHM - DURING CLIMBOUT PASSING 13,000 FT, NUMBER 1 ENGINE START VALVE OPEN LIGHT ILLUMINATED. ALSO, ENGINE OIL TEMP BEGAN INCREASING. CREW PERFORMED ENGINE SHUTDOWN CHECKLIST. AIRCRAFT RETURNED TO BHM AND MADE AN UNEVENTFUL LANDING. INSPECTED, MEL'D NUMBER 1 ENGINE START VALVE PER 80-2 AND CONTINUED.