Question 505Motor Plants - Assistant Engineer

70% to pass

When a nozzle tester is used to check the spray pattern of a diesel fuel injection nozzle, which of the following statements is true?

AThe valve should normally begin to open at 1/2 the popping pressure
BThe needle valve spring should always be removed first before testing
CThe needle valve should remain open after the nozzle pops open
DA serious hazard of blood poisoning exists if the fuel spray penetrates the skin of the operator
AI Explanation

The correct answer is D) A serious hazard of blood poisoning exists if the fuel spray penetrates the skin of the operator. This is correct because diesel fuel injection nozzles can produce a fine, high-pressure spray that can easily penetrate the skin. If this happens, the fuel can be absorbed into the bloodstream, leading to a serious and potentially life-threatening condition called diesel fuel poisoning or fuel sepsis. The other answer choices are incorrect because: A) The opening pressure is typically around 75-100% of the popping pressure, not 50%. B) The needle valve spring does not need to be removed for basic nozzle testing. C) The needle valve should close when the nozzle pops open, not remain open.

Want to practice with timed exams?

Download Coast Guard Exams for the full exam experience.

Get the App