Brakes Flashcards
Which of these would most likely happen if the measurement of the discs/drums are undersized?
a. Noisy brake operation
b. Brake grab or pull
c. Pulsating brake pedal
d. Low brake pedal
c. Pulsating brake pedal
The brake pedal on a vehicle with power assisted disc/drum brakes moves slowly to the floor during braking. Which of these could be the cause?
a. A leaking master cylinder primary cup
b. A leaking power brake booster
c. A leaking master cylinder residual check valve
d. An internal leak in the combination valve
a. A leaking master cylinder primary cup
On a vehicle with disc/drum brakes, the front brakes grab quickly when light pedal pressure is applied. This could be caused by a bad:
a. Proportioning valve
b. Pressure differential valve
c. Metering valve
d. Residual check valve
c. Metering valve
When the brakes are applied, a vibration comes from the front of a vehicle with a disc/drum system. Which of these could be the cause?
a. Unequal tire pressure
b. Binding caliper slides
c. Excessive rotor run out
d. A frozen caliper piston
c. Excessive rotor run out
A hydraulic brake line is leaking. Which of these is the correct repair?
a. Cut out the bad section and replace with new steel tubing using compression fittings.
b. Replace the leaking line with double flared seamless copper tubing.
c. Cut out the bad section and replace with single fared steel tubing using flare nuts and unions.
d. Replace the leaking line with double flared steel tubing.
d. Replace the leaking line with double flared steel tubing.
The term “friction” refers to:
a. The forces resisting movement between two surfaces in contact
b. The rate at which work is done
c. A force due to gravity
d. A twisting motion
a. The forces resisting movement between two surfaces in contact
Brakes convert Kinetic energy into [blank] energy.
a. Chemical
b. Potential
c. Mechanical
d. Heat
d. Heat
Kinetic friction exists between the:
a. Skidding tire and the pavement
b. Rotating tire and the pavement
c. Rotating brake drum and the brake lining
d. Both A and C
d. Both A and C
Static friction exists between the:
a. Brake shoes and moving brake drum
b. Stationary tire and the pavement
c. Rotating tire and the pavement
d. Both B and C
d. Both B and C?
not B: Stationary tire and the pavement?
Static friction is greater than kinetic friction for the same components.
a. True
b. False
a. True
Pascal’s law states that:
a. Brake fluid does not boil at low temperature.
b. A liquid can be compressed and can therefore be used to store energy.
c. A pressure exerted on a liquid is transmitted undiminished and is applied with equal force on equal area.
d. A pressure exerted on a liquid diminishes gradually, thereby allowing the liquid to dissipate energy.
c. A pressure exerted on a liquid is transmitted undiminished and is applied with equal force on equal area.
If 40 psi is applied against an area of 8 square inches, the output force exerted is:
a. 320 psi
b. 320 pounds
c. 5 pounds
d. 5 psi
b. 320 pounds
While road testing a vehicle, you notice a pull to the right when the brake pedal is first depressed and also even when the brakes are not applied. What could be the issue?
a. Conical tire on the right side
b. Worn strut rod bushing on the right side
c. Seized caliper piston on the left side
d. Restricted brake hose on the left side
e. Contaminated lining
a. Conical tire on the right side
The customer complaint is a pull to the right during first brake application and also even when the brake are not applied. After road testing you notice that the pull is worse with heavy braking and seems to be worse on rough roads. This would most likely be caused by:
a. A conical tire on the right side
b. A worn strut rod bushing on the right side
c. A seized caliper piston on the left side
d. A restricted brake hose on the left side
e. A contaminated lining
b. A worn strut rod bushing on the right side
A customer complaint is of a pull to the left on light braking and then a pull to the right when braking hard. What could be the cause?
a. Conical tire on the right side
b. Worn strut rod bushing on the right side
c. Seized caliper piston on the left side
d. Restricted brake hose on the left side
e. Contaminated lining
c. Seized caliper piston on the left side
A customer complains of a “spongy” pedal since having her front brake pads replaced on her car. The pedal was fine before the work was performed. What MIGHT be wrong?
a. A normal condition
b. Air in the hydraulics
c. Insufficient rear drum brake adjustment
d. Defective master cylinder
a. A normal condition
A vehicle with a complaint of a “spongy” brake pedal comes in. It is low and spongy and “firms up” when the pedal is “pumped” 2 or 3 times. What could be wrong?
a. A normal condition
b. Air in the hydraulics
c. Insufficient rear drum brake adjustment
d. Defective master cylinder
c. Insufficient rear drum brake adjustment
A vehicle has a low and “spongy” brake pedal that does not improve particularly when the pedal is “pumped”. This could be caused by:
a. A normal condition
b. Air in the hydraulics
c. Insufficient rear drum brake adjustment
d. Defective master cylinder
b. Air in the hydraulics
A vehicle has a brakes pedal which “sinks” slowly tot he floor on light brake application; however, the pedal seems to return to normal when the pedal is “pumped”. This could be caused by:
a. A normal condition
b. Air in the hydraulics
c. Insufficient rear drum brake adjustment
d. Defective master cylinder
d. Defective master cylinder
A motorist states that he has had to replace the brake linings on his car several times in the past year. The cause of this could be:
a. Insufficient master cylinder “free play”
b. Driver “riding” the brake pedal
c. Trouble with the power brake booster
d. Any of the above
d. Any of the above?
A motorist states that his car requires excessive brake pedal effort to stop the car and that the engine idle is rough. The most likely cause is:
a. Insufficient master cylinder “free play”
b. Driver “riding” the brake pedal
c. Trouble with the power brake booster
d. Any of the above
c. Trouble with the power brake booster
While performing a brake inspection on a vehicle equipped with Delco Morraine drum brakes, you notice that the right primary brake shoe is almost worn out but that all other brake linings have plenty of life remaining. The component that you should check first is:
a. Parking brake equalizer strut
b. Parking brake cable
c. Retracting spring
d. Star wheel adjuster
b. Parking brake cable
Parallelism of a disc brake rotor should be kept within a limit of:
a. 0.0005”
b. 0.001”
c. 0.003”
d. 0.005”
c or d
Excessive disc rotor run out will result in:
a. An oscillating steering wheel on brake application
b. A whistling noise during braking
c. Glazed linings
d. Reduced brake pad wear
a. An oscillating steering wheel on brake application
Generally, the minimum refinish thickness is [blank] than the minimum thickness specifications cast into the rotor.
a. 0.010 greater
b. 0.050 less
c. The same as
d. 0.030 greater
d. 0.030 greater
The reason for minimum rotor thickness is:
a. The rotor will warp too readily below the “discard” spec
b. An allowance must be made for rotor wear through the life of the brake job
c. A safe tolerance for “vented” rotor wear through the life of the brake job
d. All of the above
b. An allowance must be made for rotor wear through the life of the brake job
You are machining two front brake drums. When completed, their diameters should be:
a. Within 0.010 of each other
b. Below the maximum diameter spec. cast into the drum
c. Within 0.050 of each other
d. Both A and B
d. Both A and B
Uneven disc brake pad wear could NOT be caused by:
a. Seized caliper slides
b. Seized caliper piston
c. Warped rotor
d. Blocked hydraulic hose
c. Warped rotor
Brake pull could NOT be caused by:
a. Worn suspension parts causing caster changes during braking
b. A defective hydraulic hose
c. A seized or worn wheel brake parts
d. Air in the system
a. Worn suspension parts causing caster changes during braking
Front brake noise could NOT be caused by:
a. Loose outer pad mounting
b. Glazed, cracked or contaminated pads
c. Anti squeal hardware damaged or missing
d. Air in the system
d. Air in the system
A spongy brake pedal is most often caused by:
a. Soft linings
b. Compressing the fluid
c. Air in the system
d. Improper pedal clearance
c. Air in the system
When bleeding the brakes on a vehicle, which wheel brake should be bled first?
a. Either front wheel brake
b. Either rear wheel brake
c. The closest cylinder on the primary side of the master cylinder
d. The farthest cylinder on the primary side of the master cylinder
d. The farthest cylinder on the primary side of the master cylinder
A low brake pedal could be caused by:
a. Worn primary cup in the master cylinder
b. Linings out of adjustments
c. Overheated brake drums
d. Any of the above
b. Linings out of adjustments
While checking the brake fluid level, you notice that the rubber gasket is swollen and distorted. The:
a. Fluid could be contaminated by oil
b. System is designed to use mineral oil
c. Gasket is made from incorrect material
d. Brake fluid has been too hot
a. Fluid could be contaminated by oil
A customer complains that when stopped at a street light while holding the brakes applied the brake pedal “sinks” slowly to the floor. The most probable cause is:
a. Compensating port plugged
b. Secondary seal leaking
c. Primary seal leaking
d. Low on brake fluid
c. Primary seal leaking
A customer complains that when stopped at a street light while holding the brakes applied, the brake pedal “sinks” slowly to the floor. Brake fluid is found to be leaking into the brake booster. The most likely cause is:
a. Compensating port is plugged
b. Secondary seal is leaking
c. Primary seal is leaking
d. Low brake fluid
b. Secondary seal is leaking
A vehicle experiences front disc brake engagement prior to rear drums. The most probably cause is [blank] valve failure.
a. Proportioning
b. Metering
c. Differential
d. Quick take up
b. Metering
You are servicing rear brakes that are “locking up” during medium to hard braking. The most probable cause is [blank] valve failure.
a. Proportioning
b. Metering
c. Differential
d. Quick take up
a. Proportioning
When applying brakes on a car equipped with vacuum assist brakes, there is no assist and the engine runs rough. The cause could be:
a. Vacuum valve stuck open
b. Atmosphere valve stuck open
c. The diaphragm is leaking
d. Both A and B
c. The diaphragm is leaking
A driver exerts 100 pounds of force on a brake pedal that has a mechanical advantage of 3:1. This force is applied against a master cylinder piston of 1.5 sq in. The pressure obtained is:
a. 300 psi
b. 225 psi
c. 200 psi
d. 450 psi
c. 200 psi
The reason that front brakes are generally larger than the rear is:
a. During braking, the vehicle’s weight shifts to the front.
b. To keep rear un-sprung weight to a minimum.
c. Rear brakes would be too powerful with weight in the trunk.
d. Vehicle weight must be greater in the front that the rear to prevent understeer.
a. During braking, the vehicle’s weight shifts to the front.
Hygroscopic describes a substance that:
a. Is a good hydraulic brake fluid
b. Has an affinity towards water
c. Performs well when mixed with water
d. Can only be seen when in the presence of water
b. Has an affinity towards water
Brake fluid that has absorbed moisture will:
a. Have its boiling point lowered
b. Have its boiling point raised
c. Separate and cause a hydraulic lock
d. Cause stainless steel hydraulic parts to rust
a. Have its boiling point lowered
Brake hydraulic lines are not made of copper because:
a. They would be too expensive
b. The lines would not hold their shape
c. The flares would not hold their shape under high pressure
d. Copper work hardens and could crack
d. Copper work hardens and could crack
The compensating port provides a passage between the:
a. Low and high pressure chambers
b. Reservoir and low pressure chambers
c. Reservoir and high pressure chambers
d. Low pressure chamber and secondary seal
c. Reservoir and high pressure chambers
Serious damage may result to the rubber seals of a hydraulic brake system due to the presence of:
a. Air
b. Brake fluid
c. Mineral oil
d. Water
c. Mineral oil
During normal operation, the secondary piston in a dual master cylinder is actuated by:
a. The pedal push rod
b. The primary piston
c. Hydraulic pressure
d. None of the above
c. Hydraulic pressure
In a dual brake system, the warning light is activated by:
a. Movement of the pressure differential valve
b. Application of spring pressure
c. Pressure drop across the metering valve
d. Movement of the master cylinder piston
a. Movement of the pressure differential valve
Disc brake pads maintain a slight operating clearance with the rotors due to the action of the:
a. Air being forced between them
b. Retracting springs
c. Sliding calipers
d. Piston seals
d. Piston seals
A late model FWD vehicle that retains approximately 50% stopping power after a hydraulic failure is probably equipped with a [blank] brake system.
a. Single
b. Front/Rear split
c. Diagonal split
d. Triangular split
c. Diagonal split
“Brake fade” can be defined as the reduction in friction between brake lining and drum due to:
a. High heat generation
b. The gradual wearing of the lining
c. Low master cylinder reservoir fluid level
d. Brake pedal sinking slowly to the floor
a. High heat generation
In addition to asbestos, an organic friction material usually contains:
a. Pheonlic resins
b. Powdered metals
c. Curing agents
d. All of the above
d. All of the above
Asbestos dust is dangerous because it:
a. Is corrosive to the skin
b. Makes you sneeze
c. Is a known carcinogen
d. Is flammable
c. Is a known carcinogen
Electric brakes are popular on holiday trailers because they:
a. Hold better than hydraulic systems
b. Are not as noisy as other systems
c. Are easy to connect and do not disturb the hydraulic system on the car
d. Are lighter
c. Are easy to connect and do not disturb the hydraulic system on the car
If an open circuit occurs in the electromagnet in an electric foundation brake assembly, the resulting action would be that the brakes:
a. Apply fully and lock on
b. Drag in the release position
c. Remain fully released
d. Only come on in a panic stop
c. Remain fully released
The main difference between tire “lock” and tire “skid” is that:
a. Locked tires usually refers to a tire that can still stop, where a skidding tire doesn’t
b. Locking tires most often slide sideways, where a skidding tire doesn’t
c. Locked tires allow steering to be unhindered, while skidding tires prevent controlled steering
d. Skidding tires may still rotate, while locked tires don’t
d. Skidding tires may still rotate, while locked tires don’t
If an ABS system has a three channel output, this means that:
a. There are two speed sensors
b. The front brakes are controlled separately and the rear brakes as a pair
c. All four wheel brakes are controlled independently
d. The wheel brakes are controlled independently
b. The front brakes are controlled separately and the rear brakes as a pair
In most cars, the amber ABS light warns of a failure in the:
a. Brake hydraulic system
b. EBCM or one of its circuits
c. Mechanical portion of a control valve assembly
d. All of the above
b. EBCM or one of its circuits
In most ABS equipped vehicles, the red brake light warns of a failure in the:
a. Brake hydraulic system
b. EBCM or one of its electrical circuits
c. Electrical portion of a control valve assembly
d. All of the above
a. Brake hydraulic system
In order to generate a proper signal at the wheel sensor in an ABS system, which of the following is critical?
a. Correct air gap at the wheel speed sensor, continuity of PMG and wheel rotation
b. Speed of rotation of the drive shaft, and same size tires
c. Voltage at the battery must be 12.6 V and having the key “on”
d. Number of teeth on the speed sensor must match the PMG
a. Correct air gap at the wheel speed sensor, continuity of PMG and wheel rotation
A vehicle has “metallic” brake pads and the complaint is a “grinding” noise that is present when cold and seems to disappear as the brake temperature increases. This is caused by:
a. A normal condition
b. Wear indicators contacting the rotor
c. Anti squeal hardware defective
d. Heat glazed brake pads
e. Pads worn down to the rivets
f. Both C and D
a. A normal condition
A customer states that a “squeal” is present while driving that disappears when the brakes are applied. The most probably cause is:
a. A normal condition
b. Wear indicators contacting the rotor
c. Anti squeal hardware defective
d. Heat glazed brake pads
e. Pads worn down to the rivets
f. Both C and D
b. Wear indicators contacting the rotor
When road testing a vehicle, you notice a “squeal” that is only present when braking quite hard and more noticeable when the brakes heat up. What could be the cause?
a. A normal condition
b. Wear indicators contacting the rotor
c. Anti squeal hardware defective
d. Heat glazed brake pads
e. Pads worn down to the rivets
f. Both C and D
d. Heat glazed brake pads
A “squeal” is present when braking quite hard which is more noticeable when the brakes heat up; and also during light braking. The cause would likely be attributed to:
a. A normal condition
b. Wear indicators contacting the rotor
c. Anti squeal hardware defective
d. Heat glazed brake pads
e. Pads worn down to the rivets
f. Both C and D
f. Both C and D
Heavy “grinding” anytime the brakes are applied could be:
a. A normal condition
b. Wear indicators contracting the rotor
c. Anti squeal hardware defective
d. Heat glazed brake pads
e. Pads worn down to the rivets
f. Both C and D
e. Pads worn down to the rivets
