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Practice quizzes / Ontario Air Brake Z Test Practice Questions - Ontario Air Brake (Z Endorsement) Knowledge Test Exam / Question 160726
Practice question

What does a one-way check valve do as air leaves the supply tank?

  1. Converts service brakes into spring brakes
  2. Measures brake lining thickness
  3. Turns blue gladhands red
  4. Prevents air from returning to the supply tank

Answer: D — Prevents air from returning to the supply tank

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

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