C - Hydraulic Brake System Diagnosis and Service

Question 1

What are two Alberta Government acts, regulations, or programs relating to vehicle safety?

Answer 1

Motor Transport Act, Commercial Vehicle Inspection Program, and Commercial Vehicle Standards Alliance.

Question 2

True or False: A vehicle on which you did a brake job has been involved in an injury accident. The owner can sue your employer and you.

Answer 2

True.

Question 3

Asbestos is a health hazard. What can you do to protect yourself from this material?

Answer 3

Wear a breathing mask, as asbestos affects your lungs. Wash parts with water or a brake cleaning solution. Do not use compressed air to clean brake parts.

Question 4

Injuries can occur around heavy equipment and components. How can you protect yourself from injury?

Answer 4

Use hoists, jacks, lifting and moving equipment. Have your co-workers assist when lifting and moving large parts. Lift properly - use your legs.

Question 5

True or False: Flexible brake lines must not bulge or expand outward under high pressure applications.

Answer 5

True.

Question 6

What is meant by the term Maximum Diameter as it relates to brake drums?

Answer 6

This is the greatest diameter recommended by the vehicle manufacturer (discard diameter).

Question 7

What is meant by the term Minimum Thickness as it relates to brake rotors?

Answer 7

This is the thinnest the rotor can be as recommended by the manufacturer (discard thickness).

Question 8

What or who are your sources of information regarding a customer’s vehicle brake problem(s)?

Answer 8

A vehicle operator, a service operator, a work order, your own observations on a walk-around, and a road test.

Question 9

What two methods can you use to detect equipment problems once a customer brings a vehicle to your shop?

Answer 9

Vehicle walk around; look and touch. Vehicle road tests, listen and feel.

Question 10

What safety precautions should you observe before working on or under a vehicle?

Answer 10

Use recommended jacking points and an adequate capacity jack or hoist to lift the vehicle. Place on correct capacity axle stands. Use proper lifting and moving equipment.

Question 11

Why would you only work on one brake assembly at a time on the same axle?

Answer 11

The assembled side is a reference for checking your work.

Question 12

True or False: Drum diameter, out-of-round and taper are three checks used to determine brake drum condition?

Answer 12

True

Question 13

True or False: A brake drum that has a crack in it can be welded and returned to service.

Answer 13

False, Never weld a brake drum.

Question 14

A new brake drum and a used brake drum can be used on the same axle? Explain your answer.

Answer 14

Not normally unless the worm drum is within 0.010” (0.254 mm) of the new drum diameter.

Question 15

After machining, brake drums should be sanded with a 240 grit sandpaper. Why is this done?

Answer 15

This removes cutting grooves and creates a non-directional finish so the shoes do not move sideways during application.

Question 16

True or False: If brake return springs are discoloured and slightly bent, they can be safely straightened and returned to service.

Answer 16

False, Springs will fail in service or not provide proper tension.

Question 17

True or False: Grease or oil on brake linings or on drum or disc friction surfaces can be wiped off with Varsol and the parts will remain serviceable.

Answer 17

False, Varsol itself is oil based and will contaminate linings and friction surfaces.

Question 18

During inspection, brake rotors are measured for:

Answer 18

Parallelism, lateral run-out, and rotor thickness.

Question 19

What two methods are used to mount brake linings to brake shoes and brake pads?

Answer 19

Bonding and riveting.

Question 20

Prior to pad removal and caliper disassembly, what precaution should b taken before pushing the pistons back into the caliper bores?

Answer 20

Remove about 1/2 the volume of brake fluid from the disc brake reservoir in the master cylinder.

Question 21

When the caliper is unfastened from the anchor plate, what safety precaution should be taken before pushing the pistons back into the caliper bores?

Answer 21

Hang the caliper from a stable point to prevent damage to the flex hose

Question 22

True or False: Rotor thickness should be the same from one side of the vehicle to the other on the same axle.

Answer 22

True.

Question 23

True or False: Wheel bearings which are adjusted too loosely can have a negative effect on braking.

Answer 23

True.

Question 24

Why are wear indicators used with disc brake pads?

Answer 24

Wear indicators provide an audible and/or visual warning or reduced pad lining thickness. This helps prevent rotor damage.

Question 25

True or False: The diaphragm seal between the filler cover and the master cylinder body prevents outside air from contacting the brake fluid. This prevents water vapour from contaminating the brake fluid.

Answer 25

True.

Question 26

True or False: Aluminium master cylinders and aluminium wheel cylinders should not be honed as part of a repair process.

Answer 26

True.

Question 27

What fluid is suitable for use when honing a brake cylinder?

Answer 27

Brake fluid.

Question 28

True or False: Grease or oil on rubber brake parts poses no problem for the parts or the system.

Answer 28

False, Grease and oil can cause rubber parts to swell.