Question 59Motor Plants - Assistant Engineer70% to pass
The control rack to a unit injector regulates fuel delivery by_______________.
AI Explanation
The correct answer is B) rotating the plunger and position of the helix.
The control rack of a unit injector regulates fuel delivery by rotating the plunger, which in turn alters the position of the helix. This changes the effective length of the plunger's stroke, thereby controlling the amount of fuel injected into the cylinder. Rotating the plunger and helix is the primary mechanism used to regulate fuel delivery in unit injectors, making B the correct choice.
The other options are incorrect because they do not accurately describe the mechanism used in a unit injector. Altering spring tension (A), regulating check valve lift (C), or changing the actual plunger stroke length (D) are not the primary means of fuel delivery control in this type of system.
Related Questions
#57 The amount of fuel delivered by a unit injector is controlled by the_______________. #58 In a unit injector, an upper helix and lower helix are machined in the lower part of the plunger for _______________.#60 Which type of diesel engine fuel nozzle is shown in the illustration? Illustration MO-0059 #61 A main propulsion diesel engine is normally shutdown by _______________.#62 The overspeeding of the diesel engine driving an electric generator could cause _______________.