During a surge bleeding procedure: (hint: surge bleeding is manual bleeding)
A) the end of the bleeder hose must be kept above the level of the fluid in the container
B) pump the pedal quickly several times with the bleeder screw closed.
C) pump the pedal quickly several times while opening the bleeder screw.
D) decrease the pressure bleeder chamber pressure to 10 psi (69 kPa).
B is correct.
Surge bleeding is a method in which the pedal is pumped hard several times with the bleeder closed.
Brakes entirely rely on their coefficient of _________ by applying a mechanical force that converts to heat energy.
Friction
There are signs of paint removal and peeling on the power brake booster right below the master cylinder. Which of these would be the most likely cause?
A) A leaking master cylinder piston cup
B) A defective diaphragm in the brake booster
C) Incorrect master cylinder pushrod adjustment
D) Fuel being drawn into the booster by vacuum
Answer A is correct. A leaking master cylinder piston cup will cause an external leak at the rear of the master cylinder
Bleeding brakes is an essential routine service to maintain parts and components. A finished service comes from:
A) Removing 2 ounces of fluid from the reservoir
B) Bleeding only the front axle
C) Bleeding the front and rear for 0.5 hours
D) Bleeding all excessive air and contaminated fluid from the system
The correct answer is D) - The job isn't finished until all contaminants and air is purged from the system.
All four wheels spin freely on a rear-wheel drive vehicle that is raised off the ground. The brake pedal is depressed momentarily and then released. All wheels now spin freely except for the right front. The cause of the problem could be a:
A) faulty proportioning valve.
B) missing flex hose sealing washer.
C) seized equalizer.
D) restricted flex hose.
Answer D is correct. A restricted brake hose may force hydraulic fluid pressure through the flex hose and apply the brake, but may retain the fluid pressure in the caliper when the brake pedal is released.
After the brakes have been bled, the next thing to do before driving the car is to...
A) back off the drum brake star adjusters one full turn to avoid brake drag.
B) road-test the vehicle.
C) pump the brakes several times and check for leaks.
D) move the vehicle back and forth several times applying the pedal hard to set the brake self-adjusters.
Answer C is correct. After cleaning all of the wheel areas with brake cleaner, the brake pedal should be pumped several times.
The ________ valve is responsible for preventing brake dive.
The ________ valve is responsible for rear wheel lockup.
The metering valve is responsible for preventing brake dive.
The proportioning valve is responsible for rear wheel lockup.
A red brake light warning is illuminated on the car. This can be caused by the following EXCEPT:
A) a leaking wheel cylinder
B) a leaking brake hose
C) a seized brake caliper
D) a faulty master cylinder
A seized brake caliper
Rotor runout is usually considered excessive at two-thousandths. This is represented as:
A) 0.2
B) 0.002
C) 2
D) 0.0002
B - 0.002
The brakes are dragging (failing to release completely) on a vehicle. This could be caused by:
A) overfilled master cylinder reservoir.
B) brake fluid contamination.
C) bypassing master cylinder.
D) quick take-up valve stuck open.
Answer A is correct. An overfilled master cylinder reservoir would not allow for fluid expansion, which could cause the brakes to self-apply as the fluid heated and expanded, resulting in brake drag
The master cylinder pushrod should be adjusted:
A) until there is a slight gap between the pushrod and master cylinder piston.
B) until the piston is pushed in slightly
C) to keep slight pressure in the hydraulic system
D) as part of routine maintenance.
until there is a slight gap between the pushrod and master cylinder piston.
This term refers to when there is too much heat built up in a brake system, and outgassing of the brake pads results in an air bearing.
Brake fade
Fluid drips on the carpet when the brake pedal is depressed on a vehicle with manual brakes. Which of the following is the cause?
A) a leaking master cylinder cup
B) a torn input pushrod boot
C) an overfilled master cylinder
D) a leaking take-up valve
A leaking master cylinder cup
On most OEM vehicles, new brake pads are typically:
A) 4mm thick
B) 8mm thick
C) 12mm thick
D) 18mm thick
C) 12mm thick
A master cylinder assembly is being removed from a vehicle with power assist. The technician should do all of the following EXCEPT:
A) remove fluid from reservoir.
B) plug the end of each brake line.
C) use a fender cover to protect paint.
D) remove the brake pedal pushrod.
Answer D is correct. The brake pedal pushrod does not need to be removed.
When removing the master cylinder, all of the following steps must be performed EXCEPT:
A) remove the nuts securing the master cylinder to the booster.
B) plug the ends of the brake lines to prevent fluid loss.
C) disconnect the float level sensor.
D) drain the master cylinder.
Answer D is correct. Draining the master cylinder of fluid is not something that must be done
This term means that brake fluid can absorb moisture from the air
Hygroscopic
The rear wheels on a car with a disc/drum system lock up during heavy braking. This could be caused by:
A) a bad proportioning valve.
B) a bad pressure differential valve.
C) a bad metering valve.
D) leaking axle seals.
Answer A is correct. The proportioning valve is designed to prevent rear-wheel lock-up
The brake pedal pushrod should be adjusted to the master cylinder until:
A) there is a small gap between the pushrod and the master cylinder
B) there is slight pressure applied
C) there are several inches between the pushrod and the master cylinder
D) none of these
A only - there is a small gap between the pushrod and the master cylinder
A constant pressure on the brake pedal results in the pedal sinking to the floor. No fluid leaks on external brake components can be seen. This could be caused by:
A) an internal master cylinder leak.
B) a crack on the master cylinder cap.
C) a proportioning valve malfunction.
D) a metering valve malfunction.
Answer A is correct. You know this because it is the way that it is.
Technician A says there are two types of brake line flares: double and single. Technician B says there is only one acceptable type of tubing flare: the ISO flare. Who is correct?
A) Tech A
B) Tech B
C) Both
D) Neither
Answer D is correct. Neither Technician is correct. There are two types of flares used on brake lines, the double flare and the ISO flare. Single flares are never to be used on brake lines.
A brake system that is divided into two independent brake circuits (FL, RR)+(FR, LR) is referred to as a _______/________ system.
Dual/Split
A brake line has rusted and is leaking fluid. Technician A says that the bad section should be cut out and a new section of line should be installed with compression fittings. Technician B says the entire line should be replaced or the bad section replaced with a new double flared section, and connected with unions. Who is correct?
A) A only
B) B only
C) Both A and B
D) Neither A nor B
Only Technician B is correct. When a steel brake line is rusted and leaking, the entire line should be replaced, or the bad section cut out, the ends double flared, and connected with a new section of double flared line with unions.
A) 0.8
B) 0.08
C) 0.008
D) 0.0008
D) 0.0008 (rotors should be very consistent and straight)
The types of brake fluid that are petroleum based and can be mixed together are _______ & _________.
The type of brake fluid that is silicone based and cannot be mixed is _________.
Dot 3 & Dot 4 - petroleum based
Dot 5 - silicone based