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Practice quizzes / NAVTTC Auto Mechanic Practice Questions - NAVTTC Trade Test - Auto Mechanic Motor Vehicle Mechanic (Pakistan) Exam / Question 137136
Practice question

Which piston crown shape is most commonly used in direct-injection diesel engines to aid in air-fuel mixing?

  1. Flat top
  2. Dome top
  3. Piston cavity or bowl-in-piston
  4. Trunk type

Answer: C — Piston cavity or bowl-in-piston

The correct answer is shown above. Try the full quiz for additional practice.

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