Test – Air Brakes Test

1. How should you check that the spring brakes come on when the air pressure in the system drops below a certain level?

2. When should you use the parking brakes and the air brakes at the same time?

3. At 55 MPH on dry pavement, the air brake lag distance is about

4. The S-cam

5. On a long or steep downgrade, once you have reached you “safe” speed, brake until you are traveling

6. A typical air brake system is fully charged at

7. Under ideal conditions, the average driver of a truck or bus equipped with air brakes and traveling at 55 mph would require what stopping distance?

8. Which of the following can cause brakes to fail or fade?

9. If oil and water collect in the air tanks, what could happen to the brakes?

10. Which of the following is a reason that air tanks must be drained?

11. How would you check your trucks slack adjusters?

12. In what instances should you not use the parking brakes when parking

13. Some vehicles, such as buses, have a separate air tank used to _____.

14. The air compressor is an important part of the air brake system. What is the purpose of the air compressor?

15. How does letting up on the brake pedal release the brakes?

16. Compressed air usually contains what substances that are harmful to the brake system?

17. What are forced away from each other and against the inside of the brake drum by the S-cam?

18. Which of these should not be done during the final step of the basic, seven step inspection procedure?

19. To test the air leakage rate, one must turn off the engine (with a fully charged air system), turn the key to the “on” position, release the service brake, and ___.

20. How does letting up on the brake pedal release the brakes?

21. Which of these should not be done during the final step of the basic, seven-step inspection procedure?

22. On large, heavy vehicles, the parking or emergency brakes must be held on by something that cannot leak away, such as ___.

23. Tractor and straight truck spring brakes will come fully on when the air pressure drops to a range of ___

24. The total stopping distance for vehicles with air brake systems is influenced by four factors. Which of the following is not one of these factors?

25. “Pumping the brakes” or “riding the brakes” is unnecessarily pressing and releasing the brake pedal, which will cause ___.

26. What does the supply pressure gauge indicate?

27. What does it mean when the “wig wag” drops a mechanical arm into you view?

28. If parking brakes are not being used when the vehicle is parked, what must be done instead?

29. Tractor and straight truck spring brakes will come fully on when the air pressure drops to a range of …

30. What is a supply pressure gauge used for?

31. The low air pressure warning signal will come on before the pressure in the air tanks falls below ___ psi

32. In controlled braking, you

33. When testing the air leakage rate in a fully charged system, the loss rate with the service brakes fully applied should be no more than ___ psi per minute for a single vehicle and ___ psi per minute for a combination vehicle

34. All vehicles with air brakes must have a low air pressure warning signal

35. Front wheel brakes are good under all conditions

36. If you are away from you vehicle only a short time, you do not need to use the parking brake

37. How often should you drain air tanks

38. Why should you be in the proper gear before starting downhill?

39. What is a dual air brake system

40. The modulation control valve allows you to control the