Ontario Air Brake (Z) Practice Test 2

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 does the handbook call the brake hardware located at the wheels?

   1. Foundation brake components
   2. Air supply components
   3. Control valve components
   4. Service circuit components

2. If you double your vehicle's weight, what happens to stopping distance?

   1. It becomes four times longer
   2. It triples
   3. It doubles
   4. It stays the same

3. Why can a badly overheated brake drum stop touching the brake shoe?

   1. The pushrod retracts when it gets hot
   2. Air pressure falls sharply in hot weather
   3. The hot drum expands away from the shoe
   4. The shoe shrinks as it cools down

4. What happens if pushrod stroke goes beyond the chamber's capacity?

   1. No more brake force is produced
   2. Brake force doubles
   3. The chamber vents to the air
   4. The spring brakes release

5. During the low-air warning test, what must the ignition be?

   1. Off, with the engine stopped
   2. Off, with the battery disconnected
   3. On; the engine may run or be off
   4. On, with the engine at 1,200 rpm

6. What can happen if the trailer supply and service lines are cross-connected?

   1. Spring brakes may stay on; air is lost
   2. Only the trailer ABS light comes on
   3. The trailer brakes work twice as hard
   4. Nothing; the valves correct it automatically

7. How is a wedge brake applied?

   1. Pads clamp both faces of a spinning rotor
   2. A camshaft turns between two steel rollers
   3. A strong spring pulls the shoes inward
   4. The pushrod drives a wedge between shoes

8. You double both your load and your speed. How does stopping distance change?

   1. It becomes about four times longer
   2. It becomes about six times longer
   3. It stays roughly the same
   4. It becomes about eight times longer

9. How do you release DD3 parking brakes?

   1. Push the blue knob, then start the engine
   2. Pull the valve, then pump the pedal twice
   3. Turn the caging bolt one full turn out
   4. Operate the valve, then hold the pedal 3–5 s

10. Which drum or rotor defect must you look for?

    1. Cracks or breaks
    2. Dust on the outer face
    3. Light polishing marks
    4. Surface rust after rain

11. What powers the air compressor on a truck with air brakes?

    1. Pressure stored in the spring brakes
    2. A separate electric motor
    3. The vehicle's engine
    4. The rotation of the trailer wheels

12. After the course you get a referral envelope. How long do you have to take it to DriveTest?

    1. 6 months
    2. 2 years
    3. 30 days
    4. 1 year

13. Who can be charged for driving with brake defects or skipping required inspections?

    1. The driver and/or the operator
    2. Only the vehicle manufacturer
    3. Only the driver's trainer
    4. Nobody if no crash occurs

14. If you think the tractor has no anti-compounding valve, what should you do before applying the service brakes?

    1. Secure it and release spring brakes
    2. Run the engine at a high rpm
    3. Connect the trailer supply gladhand
    4. Open all of the tank drain valves

15. Below what supply-line pressure must trailer spring brakes apply automatically?

    1. 60 psi (414 kPa)
    2. 120 psi (828 kPa)
    3. 20 psi (138 kPa)
    4. 90 psi (621 kPa)

16. What does it mean to cage a spring brake?

    1. Lock the spring brake fully applied
    2. Drain all the air from the spring section
    3. Compress the spring so it can't apply
    4. Replace the diaphragm with a new one

17. Inspections of air-braked vehicles must be done at what frequency?

    1. Only when a warning light comes on
    2. At regular intervals set by law
    3. Only once, before first use
    4. Only after a collision

18. Which demonstration is part of the MTO air brake practical test?

    1. Changing the governor setting
    2. Measuring applied pushrod stroke
    3. Readjusting a slack adjuster
    4. Replacing a brake chamber

19. While measuring applied stroke, what should both tank gauges read when you hold the pedal down?

    1. 60 to 70 psi
    2. 140 to 150 psi
    3. 110 to 130 psi
    4. 90 to 100 psi

20. Which item must you bring to the air brake practical test?

    1. A torque wrench
    2. A tire pressure gauge
    3. Wheel chocks or blocks
    4. A spare brake chamber

21. Grease from a leaking wheel seal has reached a brake lining. Is the brake defective?

    1. No, grease actually reduces wear
    2. Only if the lining is also cracked
    3. Only if it is on the steering axle
    4. Yes, it is defective

22. You hear the supply tank safety valve venting air. What does it mean?

    1. The compressor has just reached cut-in
    2. The tanks are being drained normally
    3. Pressure is too high; repair it now
    4. The spring brakes are releasing now

23. Which of these S-cam parts is located inside the wheel rather than outside?

    1. The camshaft rollers
    2. The slack adjuster
    3. The brake chamber
    4. The pushrod

24. What is the most reliable way to inspect brake adjustment?

    1. Listen for air when braking
    2. Measure the applied pushrod stroke
    3. Check the drum temperature
    4. Feel how far the pedal travels

25. Where is compressed air turned into the mechanical force that applies a brake?

    1. In the governor on the compressor
    2. In the brake chamber at the wheel
    3. In the supply (wet) tank
    4. In the foot valve under the pedal