Effects of heat
Steels and other materials in an engine are often damaged when the engine is operated beyond, the safe temperature limits. Excessive heat in an engine causes such problems as feathered piston rings, scored cylinders, burned valves, burned piston heads, burned bearings and bushings, and a number of other possible damages. The operator of an aircraft engine, whether a pilot or mechanic, must observe carefully the all operating limitations as specified by the manufacturer.