Upgrade to remove ads
Only $0.99/month

Brake System Fundamentals

Key Concepts:

Terms in this set (45)

Brake Systems
Provide a means of using friction to either slow down, stop or hold the wheels of the car.
Brake Pedal Assembly
A lever arm to increase the force applied to the master cylinder.
Master Cylinder
Hydraulic piston type pump that develops pressure for brakes. It forces brake fluid into the brake lines.
Brake Booster
Vacuum or power steering operated device for assisting brake pedal application.
Brake Lines & Hoses
Double wall metal tubing and rubber hose for transmitting pressure to wheel brake assemblies.
Emergency or Parking Brake
Mechanical or electronic system for applying rear wheel brake assemblies.
Brake Caliper
Holds the wheel cylinder piston and brake pads.
Brake Pads
Friction members pushed against the rotor by action of the master cylinder, wheel cylinder, and piston.
Brake Rotor
Metal disc that uses friction from brake pads to stop or slow wheel rotation.
Wheel Cylinder
A hydraulic piston forced outward by fluid pressure.
Brake Shoes
Friction units pushed against the rotating brake drum by action of the wheel cylinder assembly.
Brake Drums
Rub against brake shoes to stop wheel rotation.
Hydraulic Brake System
A system that uses a liquid to transmit motion or pressure from one part to another.
Master Cylinder Reservoir
Stores the supply of brake fluid for the master cylinder.
Dual Master Cylinder
Contains two separate hydraulic piston's and two fluid reservoirs. One piston and reservoir operates two of the wheels; the other piston and reservoir operating the other two wheel cylinders.
Power Brakes
Use engine vacuum, a vacuum pump or power steering pressure to assist brake pedal application.
Hydraulic Brake Booster
Uses power steering pump pressure to help the driver apply the brake pedal. Typically found on diesel engines.
Brake Fluid
A blended hydraulic fluid that transfers pressure to the wheel cylinders. Has a high boiling point, low freezing point and absorbs water.
Longitudinally Split Brakes
Has one master cylinder piston operating the front wheel brakes and the other operates the rear brakes.
Diagonally Split Brakes
Has each master cylinder piston operating a brake assembly on opposite corners of the car.
Bleeder Screw
Allows air to be removed from the hydraulic brake system.
Anti Rattle Clips
Used to keep brake pads from vibrating and rattling.
Brake Pad Wear Sensor
A metal tab on the brake pad that informs the driver of worn brake pad linings.
Floating Caliper
Mounted on two bolts supported by rubber bushings. The caliper is free to shift or float.
Sliding Caliper
Mounted in slots machined in the caliper mounting bracket. The caliper is free to slide sideways in the slots or grooves as the linings wear.
Fixed Caliper
Normally uses more than one piston and cylinder. The caliper is bolted directly to the steering knuckle. It is NOT free to move in relation to the brake rotor.
Backing Plate
Holds the shoes, springs, wheel cylinder and other parts on a drum brakes.
Primary Brake Shoe
The front shoe, typically has a shorter lining.
Secondary Brake Shoe
The rear shoe. Typically has the largest lining.
Hold Down Springs
Hold the brake shoes against the backing plate.
Brake Ratio
The comparison of front wheel to rear wheel braking effort. Typically, 60 - 70% is done by the front brakes, while the rear brakes handle 30 - 40%.
Metering Valve
Designed to equalize braking action at each wheel during light braking applications.
Proportioning Valve
Used on systems with front disc brakes and rear drum brakes.
Anti-lock Brake System
Uses wheel speed sensors, hydraulic valves, and the on board computer to limit tire lockup and skid.
Brake Pedal Vibration
Typically caused by an out-of -round brake drum or warped brake rotor. The driver feels a chatter, pulse or shake when applying the brake.
Grabbing Brakes
A condition in which the brakes apply too quickly with only light brake pedal application. Causes include: brake booster malfunction, brake fluid or grease on the pads & shoes, worn pads and shoes or mechanical problems.
Excessive Brake Pedal Effort
An increase in the amount of foot pressure needed to apply the brakes to stop the vehicle. Causes include: frozen wheel cylinder or caliper, defective brake booster, contaminated shoes and pads.
Pulling Brakes
A symptom in which the vehicle veers to the right or left when braking. Causes include: frozen caliper or wheel cylinder piston, grease or coated pads & shoes, and incorrect front alignment.
Spongy Brake Pedal
A symptom in which the brake pedal does not feel solid when applied.The brake pedal will have to travel farther to the floor before braking action occurs. Typically caused by air in the brake system.
Dropping Brake Pedal
A symptom where the brake pedal slowly moves all the way to the floor when pressure is applied. Caused by a leak in the brake system.
Dragging Brakes
Occurs when brakes remain partially applied even though the pedal is released. Caused by frozen wheel cylinders pistons, frozen parking brake and brake fluid contamination.
No Brake Pedal
Occurs when the brake pedal goes directly to the floor with no braking action. Causes include a system leak or no brake fluid in the system.
Brake Squeek
Caused by glazed (hardened) brake linings, foreign material embedded in the linings or the wear indicator rubbing on the rotor.
Metal-On-Metal Grinding
When braking, indicating worn or no brake lining rubbing on the rotor or drum.
Bleeding The Brakes
The process of using fluid pressure (brake fluid) to force air out of the brake lines and components.
YOU MIGHT ALSO LIKE...

DedmondAutoChapter81-Brakes

46 terms
mond420

Brake System Fundamentals

60 terms
krondo

Chapter 71 Brake System Fundamentals

67 terms
atomshomcti

Auto Tech Brake Vocabulary

25 terms
alex_price98