METHODS OF INJECTION

LEARNING OBJECTIVE: Describe the principles and operation of the different diesel fuel systems.

You have probably heard the statement that "the fuel injection system is the actual heart of the diesel engine." When you consider that indeed a diesel could not be developed until an adequate fuel injection system was designed and produced, this statement takes on a much broader and stronger meaning.

In this section, various methods of mechanical injections and metering control are described. There have been many important developments in pumps, nozzles, and unit injectors for diesel engines over the years with the latest injection system today relying on electronic controls and sensors.