Brake Systems 3

Question 1

On a disc/drum system, the rear drum brakes lock up when the brake pedal is pressed hard. Technician A says the proportion inch valve may not be functioning. Technician B says the axle height valve may be out of adjustment. Who is correct?

Answer 1

Both

Question 2

While discussing quick take-up master cylinders, Technician A says this design is used with low-drag caliper pistons. Technician B says this design is only used on disc brake systems. Who is correct?

Answer 2

Both

Question 3

While manually bleeding a brake system, Technician A loosens all the brake bleeder screws at the same time. Technician B uses shop air to push the fluid and air through the lines and out the bleeder screws. Who is correct?

Answer 3

Neither

Question 4

The purpose of a pressure differential valve is being discussed. Technician A says at alerts the driver if pressure is lost and either portion of the dual braking system. Technician B says it provide the needed pressure balance between the front and the rear brakes. Who is correct?

Answer 4

A only

Question 5

Technician A says a metering valve delays front braking until the repairs are applied. Technician B says a proportioning valve controls rear brake pressure, especially during moderate stops. Who is correct?

Answer 5

A only

Question 6

Technician A says power brakes are designed with vacuum assisted units that use engine vacuum. Technician B says power brakes are designed with vacuum assisted units that use vacuum developed by and external pump. Who is correct?

Answer 6

Both

Question 7

Factors that determine a vehicles breaking power are being discussed. Technician A says the coefficient of friction between the pad and rotor or shoe and drum is a factor. Technician B says heat dissipation from brake components is a factor. Who is correct?

Answer 7

Both

Question 8

Vehicle waiting at a stop light with the brakes applied is held in place by ________ friction.

Answer 8

Static

Question 9

Technician A says the size of the pants, shoes, drums, and rotors is based on the weight of the vehicle. Technician B says their size is based on the top speed of the vehicle. Who is correct?

Answer 9

Both

Question 10

Which of the following is NOT used as a friction material in NAO brake pads?

Nut shells

Asbestos

Powdered metals

Graphite

Answer 10

Asbestos

Question 11

Organic friction material _______ semi metallic materials.

Is quieter than

Is more fade resistant than

Requires higher pedal pressure than

Answer 11

Is quieter than

Question 12

Semi metallic brake linings are being discussed. Technician A says they are more affection than organic linings at low temperatures. Technician B says they are more fade resistant then organic materials but require higher brake pedal effort. Who is correct?

Answer 12

B only

Question 13

Synthetic linings are made of _________.

Fiberglass

Aramid fiber

Both

None

Answer 13

Both

Question 14

If a force of 100 pounds is applied to a master cylinder with a piston area of one square inch, how much force is developed on a wheel cylinder that has a piston area of 2 in.²

Answer 14

300 ponds

Question 15

As brake fluid absorbs moisture, what happens to the boiling point?

Answer 15

Decreases

Question 16

A technician is diagnosing a vehicle with a braking system problem. When she removes the filler cap to check the fluid level in the master cylinder, she notices that the rubber seal on the Cap is swollen and has begun to disintegrate. What could be the problem?

Answer 16

Petroleum based lubricants and the fluid such as the wrong brake fluid

Question 17

If the master cylinder has a large rear chamber and a smaller front chamber what does the larger chamber fluid supply?

Answer 17

Front disc brakes

Question 18

Master cylinder that has a bulge at the rear, near the mounting flange, is a _______ type master cylinder.

Answer 18

Quick take-up

Question 19

An aluminum master cylinder ___.

Has a plastic fluid reservoir

Has an anodized bore

Is often called a composite master cylinder

All

Answer 19

All

Question 20

The residual pressure check valve is used in the hydraulic circuit for ______ brakes.

Answer 20

Drum

Question 21

Technician A says low-drag calipers retract the Pistons and pads farther from the rotor then traditional calipers. Technician B says systems that use low-drag calipers cannot use quick take-up master cylinders. Who is correct?

Answer 21

A only

Question 22

What are brake lines made out of?

Answer 22

Double-wall steel tubing

Question 23

A technician is diagnosing a car that had front and rear brake hoses replaced 5000 miles ago. An inspection reveals that the right front brake hose has ruptured. Technician A says the specifications called for DOT 3 fluid; using DOT 4 fluid could cause the failure. Technician B says the brake hose was twisted and stressed too much during installation. Who is correct?

Answer 23

B only

Question 24

A metering valve is found only on cars and trucks with ______.

Answer 24

Disc front and drum rear brakes

Question 25

A proportioning valve reduces fluid pressure to __________.

Answer 25

The rear brakes and during hard braking.

Question 26

Technician A says when the Brake warning light is illuminated, there is a difference in pressure between the two brake hydraulic circuits. Technician B say the Brake warning light is illuminated when the fluid level in the master cylinder reservoir is low. Who is correct?

Answer 26

Both