Air Brakes

Front 1

Spring brakes are powerful springs that are held back by air pressure. If the air pressure is removed, the springs put on the brakes.

Back 1

True******

False

Front 2

What can be done to help prevent oil and water from building up in the air tanks?

Back 2

Avoid using the brakes in humid weather.

Perform an air brake pump down test 3 times a day.

Keep light pressure on the brakes when driving through water.

Use an alcohol evaporator.

All of the above.

None of the above.********

Front 3

Brakes can fade or fail from excessive heat caused by using them too much and not relying on the engine braking effect.
(True or False

Back 3

True******

False

Front 4

Air storage tanks are used to hold compressed air.
(True or False)

Back 4

True*****

False

Front 5

The braking effect of the engine on a long steep downgrade should only be a supplement to use of brakes.

Back 5

True

False********

Front 6

A dual air brake system has two separate air brake systems, the first system is called the primary system and the other is called the secondary system.

Back 6

True*******

False

Front 7

The maximum leakage rates for an air brake system should be less than 2 psi in one minute for single vehicles and less than 3 psi in one minute for combination vehicles.
(True or False)

Back 7

True******

False

Front 8

A slack adjuster is a lever that connects the brake chamber push rod with the return spring.


True

False

Back 8

True

False******

Front 9

The safety relief valve protects the air tanks and the rest of the system from building too much pressure.


True

False

Back 9

True******

False

Front 10

Which factors will not cause brakes to fade or fail?

Back 10

A. Brakes can fade or fail from excessive heat caused by using them too much.

B. Brakes that are out of adjustment.

C. Using the engine brake and not using the brakes often enough can cause them to fail.

D. Mismatched retread tires on a trailer.

A and B.

C and D.*******

B and D.

All of the above.

Front 11

The air compressor governor controls when the air compressor will pump air into the brake safety valves.


True

False

Back 11

True

False*****

Front 12

The air compressor pumps air into the air storage tanks.


True

False

Back 12

True*****

False

Front 13

After the initial charging, the air compressor should start pumping at about 75 psi and stop at about 100 psi.


True

False

Back 13

True

False******

Front 14

What does an alcohol evaporator help prevent?

Back 14

It helps prevent water leaks.

It helps prevent air in the system.

It helps prevent dirt in the system.

It helps prevent air from leaking.

None of the above.*******

Front 15

Letting up on the brake pedal increases the air pressure and releases the brakes.


True

False

Back 15

True

False******

Front 16

Pressing and releasing the brake pedal unnecessarily can let air out faster than the compressor can replace it.


True

False

Back 16

True*******

False

Front 17

Wait for normal air pressure, release the parking brake, move the vehicle forward slowly and then apply the brakes firmly using the brake pedal best describes testing the parking brake.


True

False

Back 17

True

False********

Front 18

Step on and off the brake pedal to reduce the air tank pressure. The parking brake knob should pop out when the air pressure falls to the manufacturers specification. This is how you check which of the following?

Back 18

This is how you can check that the spring brakes will come on automatically.******

This is how you can check that the slack adjusters are adjusted properly.

This is how you can check that the supply pressure gage is working.

This is how you can check that the brake pedal is tuned properly.

None of the above.

Front 19

When testing the low pressure warning signal, turn the electrical power on and step on and off the brake pedal to reduce air tank pressure. The low air pressure warning signal must come on before the pressure drops to less than ____ psi in the air tank.

Back 19

30

45

60*********

90

100

Front 20

All trucks, tractors, and buses must be equipped with emergency brakes and parking brakes.


True

False

Back 20

True*****

False

Front 21

Only a certified mechanic can check slack adjusters.

Back 21

True

False*****

Front 22

A supply pressure gauge indicates how much pressure is in the air lines.

True

False

Back 22

True

False******

Front 23

All air brake systems have an alcohol evaporator to put alcohol into the air system.

True

False

Back 23

True

False*****

Front 24

Having ABS brakes only on one axle still gives you more control over the vehicle during braking than a vehicle without ABS.


True

False

Back 24

True*****

False

Front 25

All vehicles with air brakes must have a low air pressure warning signal.


True

False

Back 25

True******

False

Front 26

How often should you drain air tanks?

Back 26

Every hour or 100 miles.

Every 2 hours or 150 miles.

Every 3 hours or 200 miles.

Every 4 hours or 300 miles.

None of the above.*********