What was found
ON TAKEOFF ROLL, ANTI-ICE DUCT OVERHEAT LIGHT ILLUMINATED. ALL ANTI-ICE SWITCHES CLOSED. ENIGNE NR 3 ANTI-ICE DUCT TEMP SHOWED APPROX 50 DEGREES HIGHER THAN NR 1 AND NR 2 ON TAXI IN. AIRCRAFT MADE AN UNEVENTFUL RETURN TO BLOCK. REMOVED AND REPLACED RIGHT PACK TURBIN INLET OVERHEAT SWITCH. RIGHT PACK OPERATIONALLY CHECKS GOOD DURING GROUND OPERATION. AIRCRAFT RETURNED TO SERVICE. (M)