Question 1

A car with a broken timing belt is towed to your shop. The tow truck operator set the parking brake. The vehicle has an automatic vacuum parking brake release. Because the engine can't be started, the brakes won't release. How do you get the car into the shop?
A)Back off the parking brake cable at the equalizer bar
B)Back off the star wheel adjusters
C)Raise the rear wheels with a floor jack and push the vehicle on the jack
D)Pull the manual release lever on the side of the parking brake pedal assembly

Accepted Answer

Pulling the manual release lever on the side of the parking brake pedal assembly is the correct method for releasing the parking brake when the automatic vacuum release system does not work due to the engine being unable to start. This manual release lever is specifically designed for such situations.

Question 2

A clicking noise heard when the brakes are applied could be caused by ______.
A)frozen star wheel
B)play in the attachment of the pad or shoe
C)brake fluid or grease on the linings
D)scored drums

Accepted Answer

Play in the attachment of the pad or shoe can cause a clicking noise when the brakes are applied, as the movement of the loosely attached components creates an audible sound.

Question 3

Technician A says the anchor pin acts as a brake shoe stop. Technician B says the return springs on a duo-servo brake are hooked over the anchor pin. Who is correct?
A)A only
B)B only
C)both A and B
D)neither A nor B

Accepted Answer

The anchor pin serves as a brake shoe stop and the return springs on a duo-servo brake are indeed hooked over the anchor pin.

Question 4

What tool is used to adjust the brake shoes before the drum is installed?
A)drum micrometer
B)dial indicator
C)dial caliper
D)shoe set gauge

Accepted Answer

A shoe set gauge is specifically designed to adjust the brake shoes to the correct distance before the drum is installed, ensuring proper fit and function.

Question 5

During a brake inspection, the technician discovers that the right rear brake shoes are soaked with a liquid. Technician A says the wheel axle seal is leaking. Technician B says the wheel cylinder is leaking. Who is correc t?
A)A only
B)B only
C)both A and B
D)neither A nor B

Accepted Answer

Both Technician A and Technician B could be correct because brake shoes can be soaked due to a leaking wheel axle seal or a leaking wheel cylinder.

Question 6

Before removing the drum on a nondriven wheel, you should remove _____________.
A)the dust cap
B)the cotter pin and castellated nut
C)the thrust washer and outer wheel bearing
D)All the answers are correct.

Accepted Answer

Before removing the drum on a nondriven wheel, it is necessary to remove the dust cap, the cotter pin and castellated nut, and the thrust washer and outer wheel bearing. These components secure the wheel and must be removed to access the drum.

Question 7

Wheel cylinders should be rebuilt or replaced if _____.
A)substantial amounts of brake fluid are found inside the boots
B)wheel cylinder pistons are binding in their bores
C)the brake has been contaminated with petroleum-based lubricants
D)All the answers are correct.

Accepted Answer

Wheel cylinders should be rebuilt or replaced if substantial amounts of brake fluid are found inside the boots, if wheel cylinder pistons are binding in their bores, or if the brake has been contaminated with petroleum-based lubricants. All these conditions can impair the proper functioning of the brake system.

Question 8

A customer complains that the car pulls to the left during hard braking. An inspection shows that the front pads and rear shoes are worn. After resurfacing the rotors and drums and replacing the pads and shoes, a road test reveals that the car still pulls to the left during hard braking. Technician A says the wheel alignment should be checked. Technician B says the tires could be the problem and should be swapped left to right to check whether the direction of the pull changes. Who is correct?
A)A only
B)B only
C)both A and B
D)neither A nor B

Accepted Answer

Both technicians are correct. Wheel alignment issues can cause a car to pull to one side during braking, and tire problems, such as uneven wear or incorrect pressure, can also cause this issue. Swapping the tires from left to right is a diagnostic method to determine if the tires are the cause of the pull.

Question 9

Technician A says the leading shoe in a non-servo brake does most of the work when the brakes are applied while in reverse. Technician B says the trailing shoe does most of the work when the brake are applied while moving forward. Who is correct?
A)A only
B)B only
C)both A and B
D)neither A nor B

Accepted Answer

The answer of Technician A says the leading shoe in...

Question 10

The left rear brake drum is scored, but the right rear drum looks as good as new. Technician A says the left-side drum should be resurfaced and the right-side drum should be reinstalled without resurfacing. Technician B says both sides should be remachined to a similar diameter. Who is correct?
A)A only
B)B only
C)both A and B
D)neither A nor B

Accepted Answer

For optimal braking performance and safety, it's important to have both rear brake drums machined to a similar diameter. This ensures even braking and prevents potential issues that could arise from having one side wear differently than the other.

Question 11

Technician A says self-adjustment occurs on most duo-servo brakes whenever the foot brake is applied while backing up. Technician B says self-adjustment occurs on a non-servo brake whenever the foot brake is applied when driving forward. Who is correct?
A)A only
B)B only
C)both A and B
D)neither A nor B

Accepted Answer

Technician A is correct because self-adjustment in most duo-servo brake systems occurs when the brakes are applied while the vehicle is backing up. Technician B is incorrect because non-servo brakes typically adjust when the brakes are applied, not specifically when driving forward.

Question 12

What must be done first to remove a brake drum that is ridged and cannot be pulled past the edge of the shoes?
A)loosen the parking brake cables
B)manually retract the star wheel adjuster
C)pry the drum off with a large screwdriver
D)remove the drum with a slide hammer

Accepted Answer

Manually retracting the star wheel adjuster is necessary to decrease the tension on the brake shoes, allowing the ridged drum to be removed more easily. This step retracts the brake shoes away from the drum's surface.

Question 13

A grinding noise when the brakes are applied could be caused by ______.
A)weak return springs
B)weak holddown springs
C)worn shoes
D)All the answers are correct.

Accepted Answer

Worn brake shoes can cause a grinding noise when the brakes are applied, as the metal backing of the brake pad may come into contact with the brake rotor.

Question 14

The last two letters printed on the edge of the shoe lining indicate ____.
A)shoe position (right-primary etc.)
B)heat resistance
C)nominal drum diameter
D)COF (coefficient of friction)

Accepted Answer

The last two letters on the edge of the shoe lining typically indicate the coefficient of friction (COF), which is a measure of the shoe's grip or traction.

Question 15

The effort of the parking brake pedal assembly or handgrip is multiplied and passed onto the rear cables by the ____________________ lever.

Accepted Answer

The answer of The effort of the parking brake pedal...

Question 16

Technician A removes brake dust from the brake assembly with compressed air. Technician B uses an OSHA-approved brake washer to clean drum brake assemblies. Who is correct?
A)A only
B)B only
C)both A and B
D)neither A nor B

Accepted Answer

Using compressed air to remove brake dust can be hazardous as it can release harmful particles into the air. OSHA-approved brake washers are designed to safely clean brake assemblies without dispersing dangerous materials.

Question 17

Non-servo type brakes are normally found on __________.
A)small, lightweight passenger cars
B)large, full-size domestic cars
C)pickup trucks and SUVs
D)vehicles that have power brakes

Accepted Answer

Non-servo type brakes are typically found on small, lightweight passenger cars because these vehicles require less braking force compared to larger vehicles, making the simpler non-servo system adequate for their needs.

Question 18

A brake inspection reveals a leaking wheel cylinder that has soaked the brake shoes with brake fluid. The shoes are virtually new, and the drums are in excellent condition. Technician A says to clean the brake assembly with an aqueous brake cleaner, then thoroughly clean the shoes with a brake cleaning solvent. Technician B says thoroughly clean the brake assembly, then install new brake shoes. Who is correct?
A)A only
B)B only
C)both A and B
D)neither A nor B

Accepted Answer

Brake fluid contamination on brake shoes compromises their ability to function properly and safely. Cleaning the shoes does not restore their original condition or ensure safe braking. Therefore, replacing the contaminated brake shoes is the correct and safe approach.

Question 19

Technician A says on a duo-servo brake the front shoe is called the primary shoe and the rear is the secondary shoe. Technician B says on a non-servo brake, the front shoe is called the leading shoe and the rear is the trailing shoe.
A)A only
B)B only
C)both A and B
D)neither A nor B

Accepted Answer

In a duo-servo brake system, the front shoe is indeed referred to as the primary shoe because it is the first to contact the drum during forward motion, and the rear shoe is the secondary shoe, which receives additional force from the primary shoe. In a non-servo brake system, the terms leading and trailing shoe are used to describe the front and rear shoes, respectively, based on their position and function during braking. Therefore, both Technician A and Technician B are correct.

Question 20

Technician A replaces self-adjusters with worn teeth. Technician B swaps the left and right side star wheel adjuster positions so that  the adjuster pawl gets an unworn surface against which to ratchet. Who is correct?
A)A only
B)B only
C)both A and B
D)neither A nor B

Accepted Answer

The answer of Technician A replaces self-adjusters with worn teeth....

Quiz 51: Drum Brakes

A car with a broken timing belt is towed to your shop. The tow truck operator set the parking brake. The vehicle has an automatic vacuum parking brake release. Because the engine can't be started, the brakes won't release. How do you get the car into the shop?

A clicking noise heard when the brakes are applied could be caused by ______.

Technician A says the anchor pin acts as a brake shoe stop. Technician B says the return springs on a duo-servo brake are hooked over the anchor pin. Who is correct?

What tool is used to adjust the brake shoes before the drum is installed?

During a brake inspection, the technician discovers that the right rear brake shoes are soaked with a liquid. Technician A says the wheel axle seal is leaking. Technician B says the wheel cylinder is leaking. Who is correc t?

Before removing the drum on a nondriven wheel, you should remove _____________.

Wheel cylinders should be rebuilt or replaced if _____.

Technician A says the leading shoe in a non-servo brake does most of the work when the brakes are applied while in reverse. Technician B says the trailing shoe does most of the work when the brake are applied while moving forward. Who is correct?

The left rear brake drum is scored, but the right rear drum looks as good as new. Technician A says the left-side drum should be resurfaced and the right-side drum should be reinstalled without resurfacing. Technician B says both sides should be remachined to a similar diameter. Who is correct?

Technician A says self-adjustment occurs on most duo-servo brakes whenever the foot brake is applied while backing up. Technician B says self-adjustment occurs on a non-servo brake whenever the foot brake is applied when driving forward. Who is correct?

What must be done first to remove a brake drum that is ridged and cannot be pulled past the edge of the shoes?

A grinding noise when the brakes are applied could be caused by ______.

The last two letters printed on the edge of the shoe lining indicate ____.

The effort of the parking brake pedal assembly or handgrip is multiplied and passed onto the rear cables by the ____________________ lever.

Technician A removes brake dust from the brake assembly with compressed air. Technician B uses an OSHA-approved brake washer to clean drum brake assemblies. Who is correct?

Non-servo type brakes are normally found on __________.

Technician A says on a duo-servo brake the front shoe is called the primary shoe and the rear is the secondary shoe. Technician B says on a non-servo brake, the front shoe is called the leading shoe and the rear is the trailing shoe.

Technician A replaces self-adjusters with worn teeth. Technician B swaps the left and right side star wheel adjuster positions so that the adjuster pawl gets an unworn surface against which to ratchet. Who is correct?