Air Brake Practice Test 04

The free Air Brake Practice Test provides detailed explanations of the correct answers, allowing you to learn from your mistakes and hone your knowledge in areas where you need extra help. By taking advantage of this valuable tool, you’ll be well-equipped to pass the official air brake test and advance your driving career.

1 / 30

How many uses does the relay valve have?

Three

Four

One

Two

2 / 30

What can be accomplished by installing a control valve in the cab and a front brake limiting valve on the front axle?

To reduce the speed of the vehicle without braking

Reduce the braking effort to the front wheels

None of these

To improve vehicle mileage

3 / 30

Parking brakes should be in what position before making a service brake application?

The activated position

The release position

The resting position

The forward position

4 / 30

What should the brake chamber be fitted with to ensure debris will not enter the chamber?

A dust cap

Nothing

A fan

A filter

5 / 30

What is meant by compounding?

The force applied by the service brakes when the vehicle is fully stopped

The force applied when the air pressure is below 35 psi

The force applied by the spring brakes when the vehicle is still in motion

The force applied by the spring brakes and the service brake

6 / 30

The effectiveness of the spring parking brake depends on what?

The size of the spring

The service brake adjustment

The pressure the spring provides

The type of brakes

7 / 30

Which statement is false? How quickly the spring brakes will stop the vehicle depends on such factors as...

The weight and speed of the vehicle

The spring force of the spring brakes that have been installed

The type of spring brakes

The adjustment of the service brakes

8 / 30

What should always be done when caging the parking brake spring?

Draining the wet tank

Turning off the compressor

Blocking the wheels

Releasing the two-way valve

9 / 30

Instruction on how to cage is usually found where?

On the body of the parking brake chamber

From the carrier

From a licensed mechanic

With the vehicle's manual

10 / 30

when the brake drum has expanded because of extreme heating, when the brake drum starts to cool and contract, the pressure exerted by the spring parking brake may cause the brake drum to do what?

Crack or warp

Stop the vehicle quickly

Fall off

None of these

11 / 30

With an automatic limiting valve, brake applications between 40 psi and 60 psi are reduced to...

Less than 20%

Less than 45%

Less than 50%

Less than 60%

12 / 30

What is the danger of disassembling a spring parking brake unit?

They could break

Springs are under extreme pressure and could cause serious personal injury if disassembly is attempted

They could get stuck

There is no danger

13 / 30

. In the spring parking brake system, the brakes are applied by spring pressure and retracted by what?

Hydraulics

None of these

Spring pressure

Air pressure

14 / 30

Which statement is false? When parking a vehicle with over heated brakes...

Block the wheels

Park on level ground

Stop the engine and leave the transmission in the lowest gear

Keep the engine running between 600 and 900 rpm

15 / 30

On the pre-trip air brake inspection, you must ensure that the parking brake spring is not...

Expanded

Missing

Wrong size

Manually caged

16 / 30

The spring parking brake system can also act as what?

Hydraulic brakes

Air-over hydraulic brakes

Service brakes for the trailers

An emergency brake

17 / 30

After overheating the brake drums, when should you set the spring parking brake?

There is no longer any smoke coming from the brakes

The brakes no longer grab

After you have verified the brake drum is cool to the touch

The brake temperature gauge has a level reading

18 / 30

Some spring parking brakes can be released mechanically by doing what?

Letting them cool

Turning them up

Turning them down

Winding them off

19 / 30

The control valve is set in what position for dry road surfaces?

Wet

Rough

Normal

Smooth

20 / 30

Spring parking brake chambers should never be disassembled without first doing what?

Releasing the spring

Finding out which spring has to be caged

Compressing the spring with a caging bolt

Releasing the air pressure

21 / 30

Anytime the reservoir pressure drops to approximately 35 psi, what happens?

Nothing

The spring parking brakes will be activated

The pressure gauge activates

A warning light activates

22 / 30

Some systems may have an additional valve controlled by a blue button that applies what?

Only the tractor spring parking brakes and not the trailer spring parking brakes

The trailer spring brakes

None of these

The trailer service brakes

23 / 30

During normal service brake operation, wat happens to the parking brake spring?

It does not expand

It retracts

Nothing happens

It does expand

24 / 30

What is another word for when the spring compresses?

Pushes

Shrinks

Cages

Downsizes

25 / 30

Is the installation of spring parking brakes and their piping arrangements done the same in all vehicle air brake systems?

Yes

All but fire trucks

All but tandem trailers

26 / 30

How are the brakes caged?

With a bolt that runs beside the chamber body

With a valve that releases the spring

With a twist of the release valve

With a bolt that runs through the centre of the chamber body, which is turned to compress the spring

27 / 30

What happens to allow reservoir air pressure to flow to the spring parking brake chambers?

Opening the control valve

Closing the control valse

Releasing the foot valve

None of these

28 / 30

Where does the air in the control line 'dead end' to?

The one-way valve

The relay valve

The quick release valve

The two-way valve

29 / 30

What is an automatic limiting valve?

It will hold off brake application to the front wheels from 35 to 40 psi, depending on how it has been pre-set

It will hold off brake application to the front wheels from 0 to 10 psi, depending on how it has been pre-set

It will hold off brake application to the front wheels from 15 to 20 psi, depending on how it has been pre-set

It will hold off brake application to the front wheels from 25 to 30 psi, depending on how it has been pre-set

30 / 30

Disassembly of a spring brake chamber should be done by...

All of the above

The driver

The vehicle owner

A qualified mechanic or technician

Your score is

By WordPress Quiz plugin

Air Brake Practice Test 04

About

Practice Tests

Getting a License

Get In Touch