Air Break practice Test

Question 1

The stop light switch:

Answer 1

Turns on your brake lights to warn drivers behind you

Question 2

To test air service brakes, you should:

Answer 2

Brake firmly while slowly moving forward

Question 3

If your vehicle has an alcohol evaporator, every day during cold weather you should:

Answer 3

Check and fill the alcohol level

Question 4

The air loss for a straight truck or bus with the engine off and the brakes on should not be more than:

Answer 4

3 PSI in one minute

Question 5

If your truck has a properly functioning dual air brake system and minimum size air tanks, the air pressure should build from 85 to 100 psi in ____ seconds:

Answer 5

45

Question 6

A straight truck or bus air brake system should not leak at a rate greater than ___ psi per minute with the engine off and the brakes released:

Answer 6

2

Question 7

Excessive use of the service brakes results in overheating which can lead to:

Answer 7

Expansion of the brake drums

Question 8

The safety valve is set to automatically reduce tank pressure at what psi?

Answer 8

150

Question 9

If you must make an emergency stop, you should brake so you:

Answer 9

Can steer and your vehicle stays in a straight line

Question 10

The brake pedal in an air brake system:

Answer 10

Controls the air pressure applied to put on the brakes

Question 11

straight truck or bus air brake system should not leak at a rate of more than ___ psi per minute with the engine off and brakes released:

Answer 11

2

Question 12

To check the free play of manual slack adjusters on S cam brakes, you should park on:

Answer 12

Level ground, chock the wheels and release the brakes

Question 13

The parking or emergency brake on a heavy vehicle can only be held in position by something that cannot leak away, like:

Answer 13

Spring pressure

Question 14

Repeatedly partially releasing and pressing the brake pedal may result in:

Answer 14

A loss of brake air pressure

Question 15

The brake system that applies and releases the brakes when the driver uses the brake pedal is the ____ brake system:

Answer 15

Service

Question 16

The spring brakes on brake chambers on a straight truck will bring you to a stop when air pressure drops below ___ psi?

Answer 16

20

Question 17

Which of these is NOT a proper time to apply the parking brakes

Answer 17

If you are going to use the parking brakes you need to make sure that they will hold the weight of the vehicle

Question 18

If your truck or bus has a dual parking control valve, you can use pressure from a separate tank to:

Answer 18

Release the spring/parking brakes to move a short distance

Question 19

The S-cam:

Answer 19

Forces the brake shoes against the inside of the brake drum

Question 20

Under normal conditions, in order to engage the parking brakes, the driver:

Answer 20

Lets the air out of the brake system

Question 21

The air compressor stops pumping air at what psi?

Answer 21

125

Question 22

The braking power of the spring brakes:

Answer 22

Depends on the service brakes being in adjustment

Question 23

If your vehicle has an alcohol evaporator, it is there to:

Answer 23

Reduce the risk of icing in air brake valves in cold weather

Question 24

The air compressor governor controls:

Answer 24

When air is pumped into the air tanks

Question 25

The braking power of the spring brakes:

Answer 25

Depends on the service brakes being in adjustment