ABYC Diesel Practice Exam

When testing an injector nozzle, what should the technician test for?

1. Fuel tank pressure

2. Spray pattern

3. Cooling system integrity

4. Oil viscosity

The correct answer is: Spray pattern

When testing an injector nozzle, the primary focus is on the spray pattern. The spray pattern is critical because it directly affects engine performance, fuel efficiency, and emissions. A proper spray pattern ensures that fuel is distributed evenly within the combustion chamber, optimizing the combustion process. An irregular or poor spray pattern can result in incomplete combustion, leading to increased emissions and reduced power output. Testing the spray pattern also helps determine if the nozzle is clogged or malfunctioning. A well-functioning injector nozzle should produce a fine, atomized spray suitable for efficient combustion. Thus, assessing the spray pattern provides valuable insights into the injector's condition and its ability to perform effectively within the diesel engine system.