Cdl Air Brakes

Front 1

What does the Air compressor do?

Back 1

It pumps air into the air storage tanks.

Front 2

What should you do if the air compressor has it's own oil supply?

Back 2

Check the oil level before driving.

Front 3

What does the Air Compressor Governer do?

Back 3

Controls when the air compressor pumps air into the air storage tanks.

Front 4

What do the air storage tanks do?

Back 4

They store air. duh.

Front 5

What are the Air Tank Drains for?

Back 5

They manually drain water and oil from the air tanks.

Front 6

Why do you have to drain the air tanks?

Back 6

To prevent brake failure due to water expanding when it turns into ice during cold weather.

Front 7

What is the Alcohol Evaporator for?

Back 7

It puts alcohol into the air tank reducing the risk of ice in the air brake valves during cold weather.

Front 8

At what psi will the safety valve open to prevent too much pressure in the air brake system?

Back 8

150 psi

Front 9

What will happen if the air pressure gets too low?

Back 9

The brakes won't work.

Front 10

How do S-cam brakes work?

Back 10

They force the brake shoes away from one another and presses them against the inside of the brake drum

Front 11

How do Wedge brakes work?

Back 11

THe brake chamber push rod pushes a wedge directly between the ends of two brake shoes.

Front 12

How do Disc Brakes work?

Back 12

the pressure of the brake chamber on the slack adjuster turns the power screw which clamps the disc or rotor between the lining pads of a caliper

Front 13

What is the most common brake?

Back 13

S-cam

Front 14

What do the Supply pressure gauges tell you?

Back 14

How much pressure is in the air tanks

Front 15

What do the application pressure gauges tell you?

Back 15

How much pressure is being applied to the brake

Front 16

True or False: Low Air pressure Warnings are required on vehicles with air brakes.

Back 16

True

Front 17

At what psi must the Low Air Pressure Warning come on before?

Back 17

60 psi

Front 18

What should you do when the Low Air Pressure Warning light comes on?

Back 18

bring the vehicle to a complete stop as safely as possible

Front 19

What will cause the spring brakes to come on

Back 19

a leak in the air brake system

Front 20

At what psi will the spring brake come on?

Back 20

20-45 psi

Front 21

If the brakes are not adjusted properly which brakes will not work right?

Back 21

none of them, service, parking, and emergency

Front 22

What does the parking brake look like?

Back 22

A yellow, diamond-shaped push-pull knob

Front 23

What does the modulating control valve do?

Back 23

applies the spring brake gradually for better feel of braking action

Front 24

What do the dual parking control valves do?

Back 24

lets you release air from a separate air tank to move the vehicle in emergencies

Front 25

What is the Anti Lock Brake System (ABS)?

Back 25

A computerized system that keeps your wheels from locking up during hard brake applications

Front 26

How does the Dual Air Brake work?

Back 26

has two separate air brake systems which use a single set of brake controls

Front 27

How much psi must you let build up in a dual air brake system before you drive?

Back 27

100 psi

Front 28

What happens when one air tank in a dual air brake system is very low on pressure?

Back 28

either the front or the rear brakes will not be operating fully and it will take you longer to stop.

Front 29

What should you do when one of the air tanks in a dual air brake system loses pressure?

Back 29

bring the vehicle to a complete stop and have the air brakes system fixed.

Front 30

When should you push the clutch in a normal stop?

Back 30

when the engine rpm is down close to idle.

Front 31

What can happen when you brake hard on a slippery surface in a vehicle without ABS?

Back 31

Your wheels may lock up.

Front 32

What happens when your steering wheels lock up?

Back 32

You lose steering control.

Front 33

What happens when your non steering wheels lock up?

Back 33

You may skid, jackknife, or even spin the vehicle.

Front 34

What should you do if your Anti Lock Brake System malfunctions?

Back 34

You still have your regular brakes. Drive normally, but get the system serviced soon.

Front 35

What is controlled braking?

Back 35

apply the brakes as hard as you can without locking the wheels. If wheels lock, release the brake. Re-apply the brakes as soon as you can.

Front 36

What is Stab Braking?

Back 36

Apply your brakes all the way. Release brakes when they lock up. As soon as the wheels start rolling, apply the brakes fully again. repeat.

Front 37

Which works faster: hydraulic or air brakes?

Back 37

hydraulic brakes

Front 38

At 55 mph on dry pavement what is the air brake lag distance?

Back 38

32 feet

Front 39

At 55 mph under good conditions what is the total stopping distance?

Back 39

451 feet

Front 40

What can happen if the brakes overheat?

Back 40

brake fading or failure

Front 41

What is proper braking technique for going down a hill?

Back 41

Once in low gear, apply the brakes just hard enough to feel a definite slowdown. When your speed has been reduced to approximately 5 mph lower than your "safe" speed, release the brakes. When your speed has increased to your "safe" speed, repeat.

Front 42

When should you not use the parking brake?

Back 42

if the brakes are hot or if the brakes are very wet in freezing temperatures. Use wheel chocks instead.