A control system includes one or more processors configured to determine when to extend a life span of an engine by applying an additional restorative coating to the engine based on one or more monitored parameters of the engine. The monitored parameters include a condition of a previously applied restorative coating. The one or more processors are configured to determine the condition of the previously applied restorative coating based on an optical response of the previously applied restorative coating. The one or more processors also are configured to direct application of the additional restorative coating based on the one or more monitored parameters of the engine.