NL Air Brake Test 6
- Perfect for first-time and renewal commercial applicants, and those adding endorsements
- Based on 2024 NL commercial driver's licence manual
- Triple-checked for accuracy
- Updated for September 2024
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questions
correct answers to pass
passing score
- Why is an air dryer needed in an air brake system?
- Upon driver releasing the treadle in an air brake system, to where does the air get directed?
- What influences the quantity and size of reservoirs on a vehicle with an air brake system?
- What function does the slack adjuster perform in an air brake system?
- What does it mean if the safety valve must relieve pressure in an air brake system?
- Is it necessary to inspect automatic reservoir drain valves every day in an air brake system?
- Where would one typically find the brake chamber mounted in a vehicle?
- Where does the pressurized air go as the compressor's piston approaches its peak stroke in an air brake system?
- What is an alternate term for the supply reservoir in an air brake system?
- What function does the heater element in the purge valve perform in an air dryer?
- How is the push rod linked to the slack adjuster in an air brake system?
- What could be a possible outcome if sludge accumulated in the bottom of the air brake system's tank?
- What circumstances would prevent a compressor from being able to increase air pressure from 50 to 90 psi within three minutes?
- At what pressure is a safety valve normally set in an air brake system?
- What happens to the heated air from the compressor as it cools down in the supply reservoir?
- What is the crank arm-type lever the push rod is connected to known as in an air brake system?
- What causes the air in the air brake system's cylinder to compress?
- How is a brake chamber in an air brake system separated internally?
- Whereabouts in the air brake system would one typically install an air dryer?
- What purpose does a safety valve serve in an air brake system?
- What distinguishes the front axle brake chambers from the rear axle brake chambers in an air brake system?
- How frequently should the tanks in an air brake system be drained?
- What happens if there's a leak in the diaphragm of a brake chamber in the air brake system?
- What's another term for an automatic reservoir drain valve in an air brake system?
- What is the reason for installing the brake chamber and slack adjuster on the backing-plate of a front axle assembly?
- What are some advantages of air-over-hydraulic brake systems?
- Who is usually responsible for manual adjustment of wedge brakes?
- Which are not usually found in commercial vehicles?
- Which of these factors would not cause an automatic slack adjuster to fail in maintaining the proper slack?
- How can drivers track service tank air pressures?
- What air brake system doesn't necessitate an air brake endorsement?
- What's a type of low-pressure warning device used predominantly in old vehicles?
- Which statement is incorrect? Air over hydraulic brake systems were created for medium-weight vehicles because...
- What psi triggers the low-pressure indicator light or alarm due to overuse or leaks?
- Is it necessary to check automatic slack adjusters?
- An air-over-hydraulic brake system is most alike to which system?
- What must the low-pressure warning system comprise of?
- What does the stoplight switch do?
- What does the air line from the foot valve to the relay valve function as?
- When the warning system is triggered, what action must a driver take?
- Why is a quick release valve necessary in the braking system?
- Can a device showing application air pressure be added to the dashboard when brakes are applied?
- What should be the maximum angle between the push rod and the arm of the slack adjuster when brakes are fully applied?
- What determines the amount of heat the brakes can absorb and radiate into the surrounding air?
- Which is false? Extremely unreliable brake performance can come from...
- When the slack adjusters turn the S-cams, what happens?
- On manual slack adjusters, the adjusting bolt is turned until the brake linings touch the drums and then backed off by how much?
- Where is the one-way check valve installed?
- Which of these could cause brake fading or the reduction in braking power occur?
- Where is a relay valve usually installed?