section 5 air brakes

Question 1

what are the three different break systems of air breaks

Answer 1

Service breaks , parking breaks , and emergency breaks

Question 2

What does the service breaks do

Answer 2

Applies and releases the breaks when you use the break pedal during normal driving

Question 3

What do the parking breaks do

Answer 3

applies and releases the parking breaks when using the parking breaks control

Question 4

What do the emergency breaks do

Answer 4

uses parts of the service and parking brake system to stop in a break system failure

Question 5

what does the air compressor do

Answer 5

pumps air into the air storager tanks (Resovoir)

Question 6

what does the air compressor governor do

Answer 6

Controls when the air compressor will pump air into the air storager tanks.

Question 7

what turns the compressor on and off

Answer 7

the key

Question 8

what are air storage tanks used for

Answer 8

Air storage tanks are used to hold compressed air

Question 9

What happens when water catches in the compressed air

Answer 9

comrpressed air usually has some water and some oil in it which is bad for air breaks , water can freeze in cold weather and cause break failure

Question 10

what should you do with air tanks manually at end of shift

Answer 10

you must drain the tank yourself at the end of each shift

Question 11

What is the purpose of the alchohol evaporator

Answer 11

Puts alchohol into the system to help reduce ice in brake valves

Answer 12

Check achohol container as neccasary during cold weather

Answer 13

safety valve is installed in first tank the air compressor pumps air to

Answer 14

pushing down the brake pedal

Answer 15

pushing the pedal down harder than neccasary

Answer 16

foundation brakes are on every wheel most common being s cam drum brake q

Question 17

brake fade

Answer 17

too much heat can cause the brakes to stop working

Answer 18

when you push the brake pedak air is let out into each

Question 18

Do you need a pressure gauge?

Answer 18

all vehicles with air brakes must have a pressure gauge connected to air tank

Question 19

what does the application pressure gauge do

Answer 19

shows how much air pressure you are applying to brakes

Question 20

20 -45 psi

Answer 20

when emergency brakes apply

Question 21

55pi

Answer 21

alarm sounds before pressure falls to dangerously low

Question 22

100pi

Answer 22

governor cuts in normal pressure

Question 23

125 pi

Answer 23

governor cuts out full pressure

Question 24

150 psi

Answer 24

the safety valve releases air from tanks

Question 25

wig wag warning

Answer 25

warning for when psi is under 55

Question 26

stop light switch

Answer 26

the air brakes system warns drivers behind you when you put on the breaks

Question 27

front brake limiting valve when put on slippery reduces stopping power by how much

Answer 27

1/2

Question 28

when to use front brake limiting valve

Answer 28

never use front brake limiting valve

Question 29

what are emergency breaks and parking breaks held on by

Answer 29

mechanical spring pressure

Question 30

what holds springs together

Answer 30

Air pressure

Question 31

when will spring breaks fully come on automatically

Answer 31

spring breaks will come on fully when psi drops from range of 20-45psi

Question 32

what does the braking power of the spring brake depend on

Answer 32

the brakes being adjusted proper

Question 33

what does parking brakes look like and color

Answer 33

In newer vehicles with air brakes you put on the parking brake using a diamond shaped yellow push pull control knob

Question 34

what is compounding the brakes

Answer 34

never push down on the air brakes when springs are active or you’ll end up compounding brakes

Question 35

dual parking control valves

Answer 35

when main air pressure is lost, the spring breaks come on ,some vehicles like buses have a separate air tank for emergency

Question 36

what stops air from escaping the air tank

Answer 36

The one way check valve

Question 37

what is the wet tank

Answer 37

first tank the first one

Question 38

min psi for primary and secondary system

Answer 38

100psi

Question 39

what to do if low air pressure drops below 55

Answer 39

safely stop and park vehicle have air brake system fixed

Question 40

during step 5 of walk though inspection

Answer 40

check slack adjusters on s-cam , park on level ground , release parking brakes to adjust slackers

Question 41

how long can a crack not be on brake drums

Answer 41

half the width of the friction area