Ontario Air Brake (Z) Practice Test 3

All 25 questions in this test

Every question and its answer choices. The correct answers and explanations appear when you take the test above.

1. What are the brakes used for normal stopping called?

   1. Spring brakes
   2. Emergency brakes
   3. Parking brakes
   4. Service brakes

2. Which brake lining condition makes it defective?

   1. Dusty from normal daily use
   2. Cracked, loose or missing
   3. Warm after a short drive
   4. Slightly darker in colour

3. Which feature of S-cam brakes makes it easy to check brake adjustment?

   1. The exposed pushrod
   2. The hidden brake spider
   3. The self-adjusting wedge
   4. The sealed dust shield

4. During the tractor protection valve test, air blows out of the service line. What does it mean?

   1. The trailer brakes are applied
   2. The spring brakes need caging first
   3. The valve is working correctly
   4. That valve is defective

5. In a spring brake chamber, which section is nearest the pushrod end?

   1. The caging bolt section
   2. The spring brake section
   3. The service brake section
   4. The diaphragm vent section

6. What is the most visible and permanent sign of a long-stroke brake chamber?

   1. Square air ports
   2. A yellow clamp
   3. Round air ports
   4. A blue pushrod

7. Some tractors have a round blue knob. What does it control?

   1. The front wheel-limiting valve
   2. The trailer supply line
   3. The air dryer purge
   4. The tractor's spring brakes only

8. When does a vehicle have its full braking ability?

   1. When every brake is in adjustment
   2. Whenever the tanks are above 100 psi
   3. Whenever the ABS warning light is off
   4. Whenever the spring brakes are released

9. While driving, pressure falls below the normal cut-in setting. What should you do?

   1. Drive on until the warning sounds
   2. Stop safely as soon as possible
   3. Pump the pedal to rebuild pressure
   4. Rev the engine and keep going

10. From what age must the learning module and practical test be done every year?

    1. 70
    2. 65
    3. 80
    4. 75

11. Why can the inner parts of an S-cam brake be hard to inspect?

    1. They are sealed inside the supply air tank
    2. Shields or backing plates hide them
    3. They sit inside the service brake chamber
    4. They are covered by the slack adjuster arm

12. What must be on your Ontario licence to drive a vehicle equipped with air brakes?

    1. A Q restriction
    2. An R condition
    3. A Z endorsement
    4. A T endorsement

13. A truck does not comply with the Highway Traffic Act. Who must keep it off the road?

    1. The driver, operator and owner
    2. Only the mechanic who inspected it
    3. Only the vehicle owner
    4. Only the police officer

14. Before a test that releases the parking brakes, what keeps the vehicle from rolling?

    1. The trailer hand valve
    2. The low-air warning
    3. The tractor protection valve
    4. Wheel chocks or blocks

15. Why does the trailer supply valve usually close before the dash gauges fall to 20–45 psi?

    1. Line pressure falls faster than tanks
    2. The drain valves open before it does
    3. The gauges read the trailer tanks only
    4. The governor closes it automatically first

16. Why do hydraulic brakes act at the wheels almost instantly?

    1. Brake fluid cannot be compressed
    2. Fluid is stored under 145 psi
    3. The lines are shorter than air lines
    4. They use a stronger return spring

17. By law, what must a driver do on finding an air brake defect?

    1. Report it to the vehicle operator
    2. Ignore it if the truck still stops
    3. Report it only after a collision
    4. Fix it before the next shift

18. The low-air warning must activate before pressure in either tank falls to what level?

    1. 20 psi (138 kPa)
    2. 45 psi (311 kPa)
    3. 55 psi (380 kPa)
    4. 80 psi (552 kPa)

19. Which driving situation builds the most heat in the brakes?

    1. Repeated braking down a long hill
    2. Idling for an hour at a loading dock
    3. Cruising at a steady highway speed
    4. Driving on a flat and empty road

20. What does the trailer hand valve do?

    1. Applies only the trailer service brakes
    2. Releases the tractor's spring brakes
    3. Closes the tractor protection valve
    4. Fills the trailer air tanks quickly

21. An automatic slack adjuster keeps needing readjustment. What does that mean?

    1. The driver should adjust it every day
    2. It is working normally for its type
    3. The drum simply needs more grease
    4. It is defective; a technician must fix it

22. Why must brake linkage be readjusted at regular intervals?

    1. Diaphragms shrink in cold weather
    2. Air tanks lose capacity over time
    3. Governor settings drift each week
    4. Wear makes the stroke longer

23. Two chambers look different but are from different makers. What should you conclude?

    1. They must be different sizes
    2. One of them must be defective
    3. They cannot be on the same axle
    4. They may still be the same size

24. For the build-up test, what engine speed is used?

    1. 600 to 900 rpm
    2. 1,200 to 1,500 rpm
    3. 300 to 500 rpm
    4. Full governed rpm

25. Which statement about brake reaction time in air brake systems is true?

    1. Delay occurs only when releasing the pedal
    2. Delay happens only on older or worn trucks
    3. All air systems have a short delay
    4. Modern valves remove all delay completely