SK Air Brake Test 9 2025

1. During emergency applications, the tractor brakes can function without air loss because...
2. In a trailer that lacks spring brakes, control pressure causes the relay emergency valve to direct reservoir air from...
3. What is a bobtail proportioning relay valve?
4. During a supply reservoir air loss, what prevents primary and secondary reservoir air from escaping back to the supply reservoir and the ruptured line?
5. Is it possible to use the hand valve to apply the trailer brakes?
6. What will occur if the foot valve and the hand valve are operated at the same time?
7. What causes the expansion of a heated brake drum, which can lead to the chambers stroking further?
8. Which of the following are true about a slack adjuster?
9. You have to adjust your vehicle's brakes when the slack does what?
10. What will be the stroke of a brake chamber with 3/4 inch of slack at an 80 psi application?
11. What is the maximum stroke limit for a type-24LS air chamber?
12. In the process of adjusting brakes, why is it essential to lift the wheel to be adjusted off the ground?
13. What is the significance of LS in terms of chamber size?
14. How does the entire slack adjuster function?
15. What is the stroke limit for a type-20 air chamber?
16. Are wedge-type brakes typically associated with slack adjusters?
17. To operate a vehicle equipped with an air brake system, your licence must have
18. What is likely the most prevalent cause of braking loss?
19. If multiple attempts at adjusting the automatic slack adjusters have failed and they still remain out of adjustment, what should you do?
20. What happens to your brake lining at high temperatures?
21. What's the stroke limit for a type-30LS air chamber?
22. How frequently should automatic slack adjusters be adjusted?
23. How many brake applications of 100 psi per day are typically required to maintain proper adjustment with automatic slack adjusters?
24. If the brakes are terribly out of adjustment, how many 100 psi brake applications may it need to adjust them?
25. How much longer can the stopping distance be for a vehicle with poorly adjusted brakes, even with cold drums?
26. How much available slack does a correctly adjusted brake have?
27. Which of the following statements is not true about slack adjusters?
28. When adjusting slack, how should you manipulate the adjustment mechanism?
29. What is the usual tolerance when considering stroke limit?
30. How do excessively maladjusted brakes usually respond under normal light braking conditions?
31. What is the primary function of slack adjusters in an air brake system?
32. What is another term for the length of push-rod travel in an air brake system?
33. When does the most efficient braking in an air brake system occur?
34. When dealing with manual slack adjusters, why do you need to compare actual stroke to the recommended maximum stroke of 1 1/2 inches?
35. What is the stroke limit on a type-24 air chamber?
36. How much available stroke does a type-30 air chamber usually have?
37. What is another term often used to describe the safety valve within air brake systems?
38. In relation to a lever, what is the function of the fulcrum?
39. Following a slack adjustment, make sure that the slack adjusters
40. If you raise the engine to revs between 600 and 800 rpm, within what time frame should the air pressure increase from 85 to 100 psi?
41. What does the front axle ratio valve do?
42. When talking about a vehicle, what does the term "firewall" refer to?
43. Once brakes are adjusted, how can you check for brake contact?
44. What material is a brake drum usually made from?
45. What is the term used to describe a situation where the trailer becomes disconnected from the tractor?
46. When brakes are released, the angle created by the push rod and the slack adjuster arm should exceed how many degrees?
47. In the context of braking systems, what is meant by "air over hydraulic brakes"?
48. When performing an air brake test for a single unit during a pre-trip inspection, what is the maximum air loss allowed within one minute after a complete brake application?
49. For the governor operation during an air combination pre-trip procedure, what is the cut-in pressure usually lower than compared to the cut-out pressure?
50. In the context of air brake systems, to what does the term "brake pots" often refer?