What is defined as a parasitic load on an engine?

A parasitic load on an engine refers to any load that the engine must overcome in addition to the basic frictional load required for operation. This includes loads that consume power but do not contribute to the output or work that the engine is designed to perform. In this context, the correct response highlights that any load applied beyond the frictional load—such as those from accessories, alternators, or other engine components—constitutes a parasitic load.

Understanding this concept is crucial for engine performance evaluation, as parasitic loads can significantly affect fuel efficiency and overall power output. If an engine has to expend additional energy to overcome these loads, it can lead to decreased efficiency and increase wear on the engine components over time.

Other potential options do not accurately encompass this definition. For instance, only the load necessary for operation does not consider additional energy demands from accessories. Loads applied during start-up may also be temporary and do not necessarily reflect the ongoing parasitic loads that the engine consistently faces. Lastly, while the cooling system does represent a load on the engine, it is not solely classified as a parasitic load since it is essential for operating temperature management and engine longevity.

By focusing on the definition of parasitic load as encompassing any additional load that