Keeps overheating and turning on and off

The FIRST thing you need to dos is to MAKE SURE that you have enough ventilation for this set. Light-engine-type sets are MUCH more critical in their airflow needs--than CRT sets. IN particular...make SURE there is at LEAST 3" of space BEHIND the set, form the wall,, in PARTICULAR where the 'fan grill" is...this is the heat exhaust. AND...Make SURE that the TOP of the cabinet the set is mounted in has at least 5" of air space above, and around the back of the set.Tell me you are NOT running this set in a closed wall unit, with virtually NO airflow behind the set!! If so...be glad it is JUST shutting down and that the thermal sensor has NOT blown yet. If that does happen...the set will shut down for GOOD, until the sensor is replaced.

IF...this is NOT the issue...THEN..perhaps the fans are clogged with dust, and not properly cooling the light engine and lamp. The one above the lamp gets VERY dirty often, and will then shut down ther set.