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WorksheetsBrakes Midterm Fall 2024
Total questions: 65
Worksheet time: 54mins
What type of valve removes water and oil that may contaminate supply system air?
Drain valve
Inlet pressure regulating
Pressure protection
Turbocharger cut-off
Primary brake circuits are commonly color coded as what color air lines?
red
green
yellow
black
What controls air system pressure by stopping and starting compressor loading?
air dryer
air tank
governor
check valves
The friction generated between the moving surfaces slows down the rotation of the wheel, causing what?
Friction
Traction
Heat
Wear
What color is the octagonal-shaped trailer supply valve used to control the tractor protection system?
red
yellow
green
black
What are brake drums made of?
Plastic
Aluminum
Cast Iron
Stainless Steel
Heavily grooved or warped drums should be turned or replaced.
Turned
Replaced
Which of the following are the air couplers attached to the trailer hoses connecting the tractor and trailer air systems?
glad hands
circuits
boosters
governors
What is the function of the air dryer in the air brake system?
To cool the air before it enters the system
To increase the air pressure
To remove moisture and contaminants from the air
To control the flow of air
Brake lining can be _______ or ________.
Bonded
Welded
Riveted
Super glued
Do all return springs have the same amount of strength?
True
False
Only springs that lose their tension should be replaced.
True
False
maximum stroke length for a type 30 brake chamber
2"
1"
1/8"
3/4"
Self-adjusters are used to manually adjust the brakes.
False
True
When diagnosing a drum brake problem, you should:
Slam on the brakes at highway speed
Just start replacing the entire system
Test drive in an area with no witnesses around
Test drive to test under a variety of conditions
D.O.T. 393.47 states drum shoe's thickness can not be below ____ thickness
1/8
1/4
1/16
1"
Some drums have these to aid in cooling.
An AC duct
Trick question
Fins
Holes
What is the function of the check valve in the air brake system?
To control the flow of air
To increase the air pressure
To prevent air from flowing back into the compressor
To cool the air before it enters the system
What is the primary material used in the construction of brake pads?
Plastic
Aluminum
Cast Iron
Friction Material
What is the basic principle of air brake operation?
Friction is used to apply and release the brakes.
Electricity is used to apply and release the brakes.
Hydraulic fluid is used to apply and release the brakes.
Compressed air is used to apply and release the brakes.
Name two essential components of an air brake system .
Compressor
governor
intercooler
blower
what component stops the air compressor from charging the air system?
governor
Check valve
air dryer
none of these components
Why is it important to drain moisture from air brake systems and how can it be done effectively?
To improve fuel efficiency, and it can be done effectively by releasing air from the system
To reduce noise from the brakes, and it can be done effectively by adding water to the air tanks
To increase the speed of the vehicle, and it can be done effectively by adding more air to the system
To prevent corrosion and freezing, and it can be done effectively by regularly draining the air tanks and using air dryer systems.
Other than water, what else does a air dryer remove from the air being supplied to the brake and suspension system?
NO2
carbon
DEF
oil
What does CFM stand for?
Cubic Feet Per Minute
Chrome Fastened Mount
Cubic Feet per Mile
Cubed for Measurement
Do you have to set the cut in/cut out adjustments levels for a Governor before operation?
true
false
Another name for a "air tank" in a air brake circuit?
(a)
Which of the following is identified by the sudden exhaust of air draining from the dryer?
purging
unloading
snubbing
burnishing
Two color-coded flexible hoses connect the tractor and trailer air system. What color is used for the supply/emergency circuit?
Yellow
Red
Green
Blue
Primary brake circuits are commonly color coded as what color air lines?
Blue
Green
Black
Red
What type of valves are critical devices used to speed up the flow of air during brake applications and release?
Relay
Exhaust
Air brake
Anti-compounding
Which of the following is the source of power for the air brake system?
Actuator
Primary circuit
Air compressor
Governor
What is the name of this part?
Quick Release Valve
Air Governor
Air Dryer
Safety Valve
What is the name of this part?
Quick Release Valve
Air Governor
Air Dryer
Safety Valve
Compressors are __________.
located in the cylinder head
engine driven
normally closed
like an in-line filtration system
The air brake system for a straight truck or bus should not leak at a rate of more than _______psi per minute with the engine off and the brakes released.
3
1
2
-
Match the Following:
Rear Brake Chamber
Front Brake Chamber
Slack Adjuster
Air Governor
Governor
Most Air Governors are set to limit the air system at:
115 psi
105 psi
125 psi
130 psi
135 psi
The ____ _____ is mounted at the bottom of the air dryer, and receives air from the governor to relieve pressure from the air system.
Sync Valve
Holding Valve
Wet Valve
Heart Valve
Purge Valve
This tool is for adjusting the:
Slack Adjuster
Chamber Lock Bolt
Drum Mount
Chamber Clevise
S-Cam
This is the:
Cajun Bolt
Chamber Lock Bolt
Caging Bolt
Safety Lock
Parking Lockout Bolt
This is the ____ ____ the mechanic is wrenching on:
Slack Adjuster
S-Cam
Locking Clevis
Chamber Carrier
Pedal Linkage Interface
True or False: Brake Chamber Diaphragms can be replaced
True
False
True or False: Front Brake Chambers have parking brake capabilities.
True
False
When "Caging" a brake chamber, you are :
Overriding the Slack Adjuster.
Overriding The Parking Brake Default.
Locking the wheel, Not allowing free movement.
Blocking air from coming into the brake chamber.
Locking the Brake Drums onto the Brake Chamber
Air Dryer Purge Valves can be re-built:
True
False
Match the Following:
Air Dryer
Air Compressor
Purge Valve
AC Compressor
Treadle Valve
Match the Following:
Brake Shoe
Brake Pad
Brake Liner Gauge
Tread Depth Gauge
Ridiculous Gauge
What are These?
(a)
Match the Following
Service Brake Trailer Connection
Emergency Brake Trailer Connection
Secondary Air Tubing
Primary Air Tubing
Milli Vanilli
If air is heard leaking out of the left side hole, what can be done?
Only thing that can be done is to Replace the whole Brake Chamber
Cage the Chamber and replace the Diaphragm
Replace Both Diaphragms
Drain the air system completely and Refill the system.
Drain the Wet Tank
If air is heard leaking out of the right side hole, what can be done?
Replace the Brake Chamber
Cage the chamber and replace the diaphragm
Drain the Wet Tank
Drain the air system completely and refill the system.
Adjust the clevis so that the diaphragm is seated better
The Top Port is....
For Spring Brake Air
For mounting to the truck frame
Input from the Primary Tank
Output to
Atmosphere Exhaust
For Service Brake Air
The hole on the side of the chamber is for....
Mounting to the frame
To hold the service brake line hose clamp
To hold the Caging Bolt
To hold the slack adjuster tool
Zip Tie Mounting Point
Match the Following:
Long Stroke Chamber
Short Stroke Chamber
Manual
Automatic
Front Chamber
A substance used to remove moisture:
(a)
When inspecting a truck and oil is found inside the brake drum, the most likely cause is:
Failed Wheel Seal
Air Dryer Filter Needs to be Replaced
Brake Chamber Leaking
Brake Caliper Leaking
The last tech that replaced the brakes went to a Diddy party the night before
If oil is found in the drum and on the brake shoes:
The Wet Tank needs to be purged
The purge valve is inop
The drum needs to be replaced
The shoes need to be replaced
The primary air system is over-charging
Air Tanks should be drained daily:
True
False
The pressure at which the governor loads or starts the compressor operation:
(a)
The valve attached to the brake foot pedal :
(a)
If air is heard leaking out of the chamber when the parking brake is applied:
The diaphragm can be replaced
The relay valve is bad
The parking brake valve is bad
The chamber needs to be replaced
The slack adjuster can be adjusted to re-position the diaphragm
What is this?:
(a)
If excessive water drains from wet tank:
Replace Air Dryer filter or cartridge
Replace Air Compressor
Adjust/Replace the Governor
Keep the tank drain open and run the engine for 1 hour
Remove the tank drain and stuff paper towels in the hole
Match the Following:
Relay Valve
Quick Release Valve
ABS Valve
ABS Sensor
Air Pressure Sensor
