Brake Hydraulics: Master Fluid, Lines, and Troubleshooting

Question 1

Which of the following can be a symptom of air in the brake lines?

Accepted Answer

Spongy brake pedal

Answer

Worn brake pads

Answer

Faulty master cylinder

Answer

Leaking brake caliper

Question 2

How often is it typically recommended to replace brake fluid in most vehicles?

Accepted Answer

Every 2 years

Answer

Every 15,000 miles

Answer

Every 30,000 miles

Answer

Every 50,000 miles

Question 3

What type of brake caliper is commonly used in most modern vehicles with disc brakes?

Accepted Answer

Floating caliper

Answer

Fixed caliper

Answer

Sliding caliper

Answer

Single piston caliper

Question 4

What is the primary function of brake pads in a braking system?

Accepted Answer

To generate friction and slow down the vehicle

Answer

To absorb heat and prevent brake fade

Answer

To increase brake pedal travel

Answer

To protect the brake rotors from wear

Question 5

Identify the set of brake fluid properties critical for effective brake system operation:

Accepted Answer

High boiling point and low viscosity

Answer

Low boiling point and high viscosity

Answer

Low boiling point and low viscosity

Answer

High boiling point and high viscosity

Question 6

What is the primary purpose of a proportioning valve in a brake hydraulic system?

Accepted Answer

To adjust brake pressure distribution between front and rear brakes based on vehicle load

Answer

To distribute brake pressure evenly to all wheels

Answer

To prevent brake lock-up during hard braking on slippery surfaces

Answer

To regulate brake fluid flow to individual wheels

Question 7

What is the most common cause of brake pedal pulsation, often felt during braking?

Accepted Answer

Warped brake rotors that create uneven friction

Answer

Seized brake caliper that prevents even brake pad retraction

Answer

Faulty master cylinder that fails to generate consistent brake pressure

Answer

Low brake fluid level that reduces hydraulic pressure

Question 8

Which type of brake fluid has the highest boiling point, making it ideal for high-performance applications?

Accepted Answer

DOT 5

Answer

DOT 3

Answer

DOT 4

Answer

DOT 5.1

Question 9

What is the primary function of a proportioning valve in a brake system?

Accepted Answer

To reduce brake pressure to the rear wheels during hard braking, preventing them from locking up

Answer

To distribute brake fluid equally to all wheels

Answer

To prevent brake fade in high-performance vehicles

Answer

To compensate for uneven tire wear

Question 10

Which symptom is indicative of air trapped in the brake lines?

Accepted Answer

A spongy and soft brake pedal that travels further than usual when pressed

Answer

Increased stopping distance and longer braking time

Answer

Leaking brake fluid from the brake lines or components

Answer

A hard and stiff brake pedal that requires more effort to press

Question 11

What is the recommended procedure for bleeding a brake caliper to remove trapped air?

Accepted Answer

Open the caliper's bleed screw and repeatedly pump the brake pedal to force fluid through the system

Answer

Close the caliper's bleed screw and fill the brake master cylinder until fluid flows out of the bleed screw

Answer

Attach a pressure bleeder to the brake caliper and use compressed air to force fluid through the system

Answer

Use a vacuum bleeder to create a vacuum in the brake caliper and draw fluid through the system

Question 12

Which type of brake hose is the most durable and resistant to heat and abrasion?

Accepted Answer

Stainless steel braided hose with a Teflon lining

Answer

Standard rubber hose with wire reinforcement

Answer

Teflon hose

Answer

Nylon hose

Question 13

Which factor is the most common cause of brake fade, where the brakes lose effectiveness after repeated or extended use?

Accepted Answer

Overheated brake pads due to friction and heat buildup

Answer

Low brake fluid level due to leaks or evaporation

Answer

Air trapped in the brake lines or components, causing compressibility

Answer

Worn brake rotors due to excessive friction and heat

Question 14

Which type of brake pad material is best suited for high-performance driving, offering superior stopping power and heat resistance?

Accepted Answer

Carbon fiber brake pads

Answer

Ceramic brake pads

Answer

Organic brake pads

Answer

Semi-metallic brake pads

Question 15

What is the purpose of a brake pedal stop in a vehicle's brake system?

Accepted Answer

To prevent excessive travel of the brake pedal, ensuring it doesn't hit the floor

Answer

To adjust the height of the brake pedal for a comfortable driving position

Answer

To reduce the amount of brake force applied, preventing wheel lock-ups

Answer

To absorb impact in the event of a collision and protect the driver's feet

Question 16

To diagnose brake fluid contamination, what steps should be taken?

Accepted Answer

Inspect brake fluid for discoloration, examine brake lines and hoses for wear, and check the brake fluid reservoir for debris.

Answer

Replace brake pads, flush the brake system, and inspect brake rotors for uneven wear.

Answer

Measure fluid level, check brake fluid pressure, and inspect the master cylinder for leaks.

Question 17

What is the primary function of a proportioning valve in a brake hydraulic system?

Accepted Answer

To distribute braking forces between the front and rear wheels, preventing rear-wheel lockup during braking.

Answer

To increase brake fluid pressure

Answer

To reduce brake pedal effort

Question 18

Which material is NOT commonly used in the production of brake lines?

Accepted Answer

Polyethylene

Answer

Nickel-copper alloy

Answer

Steel

Answer

Copper

Question 19

When bleeding brakes, which wheel should be bled first?

Accepted Answer

The wheel furthest from the master cylinder

Answer

All wheels simultaneously

Answer

The wheel closest to the master cylinder

Question 20

What is the primary purpose of the residual pressure valve in a brake master cylinder?

Accepted Answer

To maintain a minimal amount of brake fluid pressure in the system when the brake pedal is released

Answer

To prevent brake fluid from leaking out of the master cylinder

Answer

To amplify brake pedal force

Question 21

What is the recommended torque value for tightening brake line fittings?

Accepted Answer

11 ft-lbs (15 Nm)

Answer

5 ft-lbs (7 Nm)

Answer

15 ft-lbs (20 Nm)

Answer

20 ft-lbs (27 Nm)

Question 22

What is the primary function of a brake booster?

Accepted Answer

To increase brake pedal force, reducing the effort required to operate the brakes

Answer

To store brake fluid

Answer

To regulate brake fluid pressure

Answer

To act as a brake pedal return spring

Question 23

Which of the following factors does NOT impact the effectiveness of a hydraulic brake system?

Accepted Answer

Brake pad wear

Answer

Corrosion or leaks in the system

Answer

Presence of air within the lines

Answer

Viscosity of the brake fluid

Question 24

In a hydraulic brake system, what is the primary role of the master cylinder?

Accepted Answer

Converting mechanical force applied to the brake pedal into hydraulic pressure

Answer

Removing air from the system

Answer

Distributing brake fluid to the wheels

Answer

Storing brake fluid

Question 25

What is the main purpose of a brake caliper in a vehicle's brake system?

Accepted Answer

Applying hydraulic pressure to the brake pads to generate friction against the rotors

Answer

Converting pedal force into hydraulic pressure

Answer

Distributing brake fluid to the wheels

Question 26

In a hydraulic braking system, what is the primary function of brake fluid?

Accepted Answer

Transmitting hydraulic pressure from the master cylinder to the brake calipers or wheel cylinders, enabling the application of braking force.

Answer

Cooling various components of the brake system

Answer

Providing lubrication for brake pads and rotors

Question 27

For contemporary vehicles, which type of brake fluid is typically recommended?

Accepted Answer

DOT 3 or DOT 4

Answer

DOT 5

Answer

DOT 5.1

Answer

DOT 1

Question 28

Why is it essential for brake lines to be constructed from corrosion-resistant materials?

Accepted Answer

To prevent the formation of rust and corrosion, which can weaken the lines, leading to leaks and compromising the integrity of the braking system.

Answer

To reduce the overall weight of the vehicle

Answer

To enhance the aesthetic appeal of the brake system

Question 29

What is the primary purpose of a proportioning valve in a vehicle's braking system?

Accepted Answer

To regulate brake pressure distribution to the rear wheels, preventing them from locking prematurely and ensuring balanced braking

Answer

To control the flow rate of brake fluid within the system

Answer

To increase the overall braking force regardless of wheel conditions

Question 30

When bleeding a brake system, why is it crucial to maintain an adequate level of brake fluid in the reservoir?

Accepted Answer

To prevent air from being drawn into the system, which can impair braking performance and cause a spongy brake pedal feel

Answer

To increase the hydraulic pressure in the system

Answer

To make it easier to detect leaks in the system

Question 31

A soft brake pedal with a long travel distance generally indicates the presence of:

Accepted Answer

Air in the brake lines.

Answer

A failing master cylinder.

Answer

Severely worn brake pads.

Answer

A malfunctioning brake proportioning valve.

Question 32

Which of the following components is not considered part of the brake hydraulic system?

Accepted Answer

Brake rotors.

Answer

Wheel cylinders.

Answer

Master cylinder.

Answer

Brake lines.

Question 33

What is the primary purpose of a brake booster in a vehicle?

Accepted Answer

To enhance the driver's ability to apply braking force.

Answer

To control the pressure of the brake fluid.

Answer

To prevent brake fade during extended braking.

Answer

To regulate the flow rate of brake fluid.

Question 34

When bleeding brake lines, the recommended sequence is to:

Accepted Answer

Start with the furthest wheel cylinder or caliper from the master cylinder and work your way towards the master cylinder.

Answer

Begin with the closest wheel cylinder or caliper to the master cylinder and progress towards the master cylinder.

Question 35

What is the generally recommended interval for replacing brake fluid?

Accepted Answer

Every 2-3 years.

Answer

Only when experiencing a spongy brake pedal.

Answer

Every 5-7 years.

Answer

Brake fluid never needs replacement.

Question 36

In a hydraulic brake system, the primary function of brake fluid is to:

Accepted Answer

Transmit pressure from the master cylinder to the wheel cylinders or calipers.

Answer

Lubricate brake components.

Answer

Cool the brake system.

Question 37

Which of the following is NOT a property of DOT 3 brake fluid?

Accepted Answer

It has a higher boiling point than DOT 4 fluid.

Answer

It is hygroscopic, meaning it absorbs moisture over time.

Answer

It is generally compatible with most rubber brake components.

Answer

It is commonly found in older vehicles.

Question 38

What is the main purpose of a proportioning valve in a brake system?

Accepted Answer

To regulate brake pressure to the rear wheels based on the vehicle's load.

Answer

To control the braking force independently on each wheel.

Answer

To prevent brake fade during hard braking.

Question 39

When bleeding a brake system, the recommended starting point is the:

Accepted Answer

Wheel cylinder or caliper furthest from the master cylinder.

Answer

Wheel cylinder or caliper closest to the master cylinder.

Answer

Front passenger-side wheel.

Question 40

A common symptom of air in a brake line is:

Accepted Answer

A spongy brake pedal.

Answer

A hard brake pedal.

Answer

Noises during braking.

Question 41

What is a common cause of brake fluid contamination?

Accepted Answer

Moisture from the air.

Answer

Coolant leaks.

Answer

Engine oil leaks.

Question 42

What is the main purpose of a brake booster?

Accepted Answer

To help the driver apply brake pressure.

Answer

To distribute brake force evenly to all wheels.

Answer

To regulate brake fluid pressure.

Answer

To prevent brake fade.

Question 43

How do you properly check brake fluid level?

Accepted Answer

With the engine off and the vehicle parked on a level surface.

Answer

With the engine running and the brakes applied.

Answer

With the vehicle jacked up and the wheels off the ground.

Question 44

What's a common cause of brake fade?

Accepted Answer

Brake components overheating.

Answer

Air in the brake lines.

Answer

Low brake fluid level.

Answer

A faulty proportioning valve.

Question 45

What is the typical operating pressure range for a brake system?

Accepted Answer

Between 500 and 1,000 psi.

Answer

Over 2,000 psi.

Answer

Between 1,000 and 2,000 psi.

Answer

Between 10 and 50 psi.

Question 46

What is the primary role of brake fluid in a brake system?

Accepted Answer

To transmit hydraulic pressure.

Answer

To protect against corrosion.

Answer

To cool the brake system.

Answer

To lubricate brake components.

Question 47

What type of brake line is most commonly found in car brake systems?

Accepted Answer

Steel.

Answer

Stainless steel.

Answer

Aluminum.

Answer

Copper.

Question 48

What is the main purpose of a proportioning valve in a brake system?

Accepted Answer

To distribute braking force unevenly between the front and rear wheels.

Answer

To prevent the wheels from locking up.

Answer

To increase brake fluid pressure.

Question 49

What is a common sign of air in the brake lines?

Accepted Answer

A spongy brake pedal.

Answer

Loud squealing noise.

Answer

Blue smoke from the brakes.

Answer

Vibrating steering wheel.

Question 50

When bleeding a brake system, what is the proper order?

Accepted Answer

Start farthest from the master cylinder and work towards it.

Answer

Start closest to the master cylinder and work away from it.

Answer

Bleed all calipers or wheel cylinders simultaneously.

Question 51

What is the primary cause of brake fade?

Accepted Answer

Overheating of the brake pads and rotors

Answer

Leaking brake fluid

Answer

Worn brake pads

Answer

Air in the brake lines

Question 52

Which of the following is NOT a type of brake fluid?

Accepted Answer

DOT 5 Silicone

Answer

DOT 3

Answer

DOT 5.1

Answer

DOT 4

Question 53

What is the purpose of a brake booster?

Accepted Answer

To increase the force applied to the brake pedal

Answer

To reduce the amount of brake pedal travel

Answer

To prevent the brakes from locking up

Answer

To cool the brake fluid

Question 54

Which of the following is a potential consequence of using the wrong type of brake fluid?

Accepted Answer

Reduced braking performance and system damage

Answer

Increased fuel consumption

Answer

Electrical system failure

Answer

Suspension problems

Question 55

What is the recommended interval for replacing brake fluid?

Accepted Answer

Every 2 years or 30,000 miles

Answer

Every 5 years or 50,000 miles

Answer

Only when the brake pedal feels spongy

Answer

Every year or 10,000 miles