SK Air Brake Test 7 2025

1. A ratio valve is used in vehicles equipped with
2. What is the primary function of a one-way check valve in an air brake system?
3. Which of the following is NOT used to warn of a low air pressure condition?
4. What is the term for when the governor initiates the compressor to enter its pumping phase?
5. What is integrated near the rear brake chambers to help correct brake lag?
6. Older trucks may have a front wheel limiting valve that is controlled by what mechanism?
7. For what primary reason is an air dryer utilized in an air brake system?
8. What is the name of the second reservoir in an air brake system?
9. Where would you normally find the one-way check valve in an air brake system?
10. If a safety valve releases excess pressure, what could this signal?
11. What is a low-pressure warning device that drops into the driver's field of vision referred to as?
12. How is the supply reservoir safeguarded from over-pressurization and possible rupture?
13. What is affixed to the surface of the brake shoes in an air brake system?
14. Why do front brake assemblies mount the brake chamber and slack adjuster on the backing plate?
15. What occurs when the air pressure in the reservoir decreases?
16. Do air dryers eliminate all moisture from the air in the brake system?
17. The tractor protection system must kick in before air pressure falls below
18. Which of the following is not true regarding the functions of a spring-brake chamber?
19. What is the main function of the tractor protection system?
20. What does the phrase 'caging the brakes' refer to?
21. What happens when air from the spring-brake circuit is released?
22. What does 'blended air' mean in the context of an air brake system?
23. What factor dictates the arrangement and installation of parking brakes and piping in a vehicle air brake system?
24. The power spring can be manually compressed using what, if air pressure cannot be restored in the service-brake chamber and the vehicle needs to be moved?
25. To prevent compounding, when should the park brake be released?
26. In a dual-circuit system, where does pressurized air move from the supply reservoir to?
27. How many key functions does the trailer-supply valve perform?
28. Who should disassemble and dispose of all discarded spring-brake chambers?
29. How many separate air chambers do spring brakes comprise of?
30. At which pressure will the spring brakes apply themselves?
31. What's the purpose of an air pressure gauge in a brake system?
32. The rear chamber, which houses a large, robust compression spring and diaphragm that serves for emergency and parking functions, is sometimes known as what?
33. What constitutes the tractor protection system?
34. What happens when you operate the park control valve?
35. A two-way check valve shifts the shuttle so that what can occur?
36. Why are spring brakes a reliable parking brake option?
37. Upon operating the park control valve, from where is air exhausted?
38. During a controlled service brake application, where does air pressure act upon that results in a specific reaction?
39. In case a failure occurs in the primary circuit and a brake application is made, control air from the secondary side of the foot valve is redirected to where?
40. After all air is lost, how can a vehicle with spring brakes still be moved?
41. Which brakes does the primary reservoir operate under normal conditions?
42. Where are spring brakes always installed?
43. What's the primary function of the dual-circuit air system?
44. Where is an anti-compound line sometimes installed in an air brake system?
45. When does compounding of the brakes occur?
46. If the air pressure in the brake system falls below roughly what pressure, the spring brake may start to drag?
47. If your unit lacks dead-end couplers, what should you do?
48. At what angle should the couplers be to each other when connecting the glad hands?
49. What is the typical profile of the trailer-supply valve?
50. What provides air to the trailer-supply valve?