11.3 Exercises for Unit 11

1. When the speed of a vehicle is doubled, the amount of kinetic energy that must be overcome by braking action is multiplied how many times?

A. 10
B. 2
C. 3
D. 4

2. The time frame between the instant the operator decides that the brakes should be applied and the moment the brake system is activated is known by what term?

A. Total reaction
B. Decision reaction
C. Operator reaction
D. Stopping reaction

3. Which factor will NOT increase braking temperatures?

A. Extreme weather conditions
B. Operator abuse
C. Load on the vehicle
D. Speed of the vehicle

4. On a typical rear-wheel drive vehicle, the front brakes will handle what percentage of the braking power?

A. 60 to 80
B. 70 to 80
C. 40 to 60
D. 40 to 50

5. Of the following functions, which is NOT a function of the master cylinder in a hydraulic brake system?

A. Develops pressure.
B. Assists in equalizing the pressure required for braking.
C. Keeps the system full of fluid.
D. Prevents fluid from seeping past the cups of the wheel cylinders.

6. Which factor is an advantage of having a dual master cylinder in a hydraulic brake system?

A. It enables the brakes to be applied with less effort.
B. There is less chance of the brakes malfunctioning.
C. It causes the brake shoes to wear longer.
D. It makes for a safer brake system.

7. What dual master cylinder system operates the brake assemblies on opposite corners?

A. Latitudinal split
B. Longitudinal split
C. Diagonal split
D. Equidistant split

8. What brake system component changes hydraulic pressure into mechanical force?

A. Wheel cylinder
B. Master cylinder
C. Combination valve
D. Brake drum

9. Brake lines are constructed from what type of tubing?

A. Seamless aluminum
B. Seamed aluminum
C. Single-wall steel
D. Double-wall steel

10. What component is used to feed two wheel cylinders from a single brake line?

A. Poppet valve
B. Counterbalance valve
C. Junction block
D. Pressure-control block

11. Which DOT rated brake fluid is easily spotted by its purple color?

A. DOT 5
B. DOT 4
C. DOT 3
D. DOT 2

12. (True or False) The primary brake shoe is the front shoe and normally has a slightly shorter lining than the secondary shoe.

A. True
B. False

13. What type of brake lining does NOT wear the brake drum excessively?

A. Metallise
B. Semi-metallic
C. Non-metallic
D. Metallic

14. What type of brake shoe adjusting system is operable in both forward and reverse directions?

A. Link
B. Lever
C. Chain
D. Cable

15. Which action is a disadvantage of drum brakes?

A. No means of adjustment
B. Brake fade
C. Decreased braking distances
D. Excessive cooling air allowed to enter the assembly

16. Which action is an advantage of disc brakes?

A. Reduces braking distances.
B. Increases brake fade.
C. Collects asbestos dust in the brake cavity.
D. Dissipates heat through the brake hub.

17. Which component is NOT part of a disc brake assembly?

A. Brake pads
B. Caliper
C. Brake hub
D. Rotor

18. What component of a caliper acts as a spring to retract the piston?

A. Dust boot
B. Piston seal
C. Boot seal
D. Caliper clip

19. Metal tabs are built into some disc brake pads for what purpose?

A. Notifying the operator of worn brakes.
B. Allowing easy installation and removal from the caliper.
C. Preventing the pads from coming out of the caliper during operation.
D. Identifying the type of lining material used on the pads.

20. What type of caliper is designed to permit equal braking force to be applied to both sides of the rotor?

A. Semi-floating
B. Semi-fixed
C. Floating
D. Fixed

21. In an antilock brake system (ABS), what component modulates the amount of braking pressure (psi) going to a specific wheel circuit?

A. Trigger wheels
B. Hydraulic actuator
C. Wheel speed sensors
D. ABS computer

22. During the operation of an antilock brake system, what component measures trigger wheel rotation?

A. Hydraulic actuator
B. ABS computer
C. Frequency reducer
D. Wheel speed sensor

23. To develop the additional force required to apply the brakes, most power brake systems use the difference between what two systems?

A. Exhaust manifold vacuum and hydraulic pressure
B. Exhaust pressure and pneumatic vacuum
C. Intake manifold vacuum and atmospheric pressure
D. Manifold air vacuum and exhaust gas pressure

24. What component is designed to make vacuum available for a short time to the booster unit should the vehicle have to stop quickly with a stalled engine?

A. Vacuum chamber
B. Vacuum reservoir
C. Vacuum valve
D. Vacuum manifold

25. Should the power steering system fail, what component of a hydraulic power booster retains enough fluid and pressure for at least two brake applications?

A. Hydraulic reservoir
B. Pressure regulator
C. Accumulator
D. Booster valve

26. (True or False) The parking/emergency brake must hold a vehicle on any grade.

A. True
B. False

27. When you are checking the fluid level in a master cylinder, how far should the fluid be from the top of the reservoir, in inches?

A. 1/4
B. 1/8
C. 1/2
D. 1/16

28. The distance from the floor to the brake pedal with the brake applied is known as the brake pedal .

A. height
B. free play
C. reserve distance
D. performance distance

29. Before installing a master cylinder on a vehicle, what action should you take?

A. Lubricate all parts with denatured alcohol.
B. Remove the inlet ports and check for obstructions.
C. Install the master cylinder clamp.
D. Bench bleed the master cylinder.

30. What action should you take when you find any pitting, scoring, or scratching in the bore of a wheel cylinder?

A. Replace the wheel cylinder.
B. Hone the cylinder bore.
C. Install a cylinder sleeve.
D. Sand the cylinder bore with emery cloth.

31. Normally, what is the maximum amount of surface material, in inches, that can be removed from a brake drum and still provide adequate braking?

A. .006
B. .060
C. .003
D. .030

32. When replacing disc brake shoes, why do you force the caliper pistons into the bores of the caliper?

A. To determine if the pistons are free to move in the caliper.
B. To open the caliper wide enough for the new thicker pads.
C. To inspect for hydraulic leaks around the piston seal.
D. To open the caliper wide enough for the removal of the rust ridge on the disc.

33. When removing air from the hydraulic brake system, you should bleed one brake at a time starting with the wheel cylinder located where?

A. Nearest to the master cylinder
B. Farthest from the master cylinder
C. On the left front
D. On the right front

34. The governor maintains the proper pressure required for safe operation by controlling what component?

A. Compressor unloader mechanism
B. Pilot valves
C. Pressure differential valve
D. Spring tube

35. What gauge should you use to adjust the type O-1 governor accurately?

A. Thickness
B. Vacuum
C. Depth
D. Air pressure

36. Within the type D governor, at what pressure range, in psi, will the air pressure allow the exhaust stem to close the exhaust valve and to open the inlet valve?

A. 80-90
B. 90-100
C. 100-110
D. 110-120

37. To increase the pressure setting of the type D governor, you must perform which task?

A. Turn the adjusting nut clockwise.
B. Turn the adjusting screw clockwise.
C. Add shims to the inlet valve guide.
D. Remove shims from the inlet valve guide.

38. What is the function of the unloader assembly?

A. To cool, store, and remove moisture from the air.
B. To protect the brake system against excessive pressure.
C. To stop and start compression in the compressor.
D. To control the air pressure that is delivered to the brake chambers.

39. What component is used to cool, store, and remove moisture from the air and give a smooth flow of air to the brake system?

A. Unloader mechanism
B. Reservoir
C. Air pressure diaphragm
D. Pressure differential mechanism

40. What is the function of the safety valve located on top of the first reservoir?

A. To prevent moisture buildup in the system.
B. To protect the system against excessive back pressure.
C. To prevent air pressure from reaching its maximum setting.
D. To protect the system against excessive air pressure.

41. What component is designed to convert the energy of compressed air into mechanical force and motion?

A. Brake valve
B. Brake chamber
C. Brake cylinder
D. Brake diaphragm

42. What component provides a quick and easy way to adjust air brakes to compensate for wear?

A. Brake camshaft
B. Adjusting screw
C. Pushrod adjuster
D. Slack adjuster

43. What valve controls the air pressure delivered to the brake chambers?

A. Tractor protection
B. Quick release
C. Treadle
D. Limiting

44. After cleaning a treadle valve, you should apply which lubricant to the internal parts of the valve during reassembly?

A. Engine oil
B. Chassis lube
C. Bearing grease
D. Vaseline

45. What valve is designed to exhaust brake chamber air pressure and speed up brake release of the air brake system?

A. Quick release
B. Treadle
C. Safety
D. Trailer control

46. All air brake assemblies used to connect air brake systems from one vehicle to another are equipped with detachable fittings and what else?

A. Quick release
B. Spring guard
C. Safety guard
D. Trailer control release

47. The low pressure warning indicator is designed to send an alarm when air pressure drops below how many psi?

A. 80
B. 75
C. 65
D. 60

48. What term refers to the basic test made to an air brake system?

A. Functioning
B. Operational
C. Pressure
D. Drop

49. On an air brake antilock brake system, the wheel speed sensors send signals to what component?

A. ABS module
B. Pulse generator
C. Tone wheel
D. Emergency relief valve

50. When wheel lock up occurs on an air brake antilock brake system, what component sends a signal to the solenoids in the modulator to release the brakes?

A. ABS module
B. Pulse generator
C. Tone wheel
D. Emergency relief valve