Section+3+Reading+Guide

> **Riveted linings** where the brake block is attached to the backing plate with a copper or aluminum rivets. The major advantage of riveting is that it allows a small amount of flex between the block and backing which absorbs vibration, but can also create stress points in the lining where cracks are likely to develop. > **Bonded linings** use high-temperature adhesive to glue the brake block directly to the show pad backing plate. Bonding offers longer service life, less risk of cracking, and less damage to the rotors (without rivets). > **Mold-bonded** linings are found on some disc brake pads. The fiction material in a mold bonded pad is cured on the backing plate during manufacture a process also called integrally molded. The uncured friction material and adhesive are forced into the holes and formed onto the plate then cured under heat and pressure which solidly lock the brake block in place. > Some friction materials used are: **Semimetallic** – commonly called semimets and is fused together without melting in a process called sintering and the result is called sintered metal linings. **Nonasbestos**, nonasbestos organic (**NAO**), or nonasbestos synthetic (**NAS**), linings are called synthetic, because aramid fibers (man-made) are used instead of metal as a base material. **Aramid** is the generic name for aromatic polyamide fibers (or **Kevlar** a Dupnt brand name and a registered trademark of E.I. Dupont de Nemours and Company). **Carbon Fiber**, CFRC (carbon fiber reinforced carbon) composed of a carbon mix into which reinforcing carbon fibers are embedded. **Ceramic friction material** contain ceramic fibers usually potassium titanite.
 * Antifriction Bearings
 * Tapered Roller Bearings
 * **Tapered roller bearings** are bearings that can take large axial forces as well as being able to sustain large radial forces. Also they are repackable bearings
 * Inner and Outer Wheel Bearings
 * most commonly a tapered roller bearing consisting of tapered rollers, matching races, and a cage. mounted on a hub, the permit the spindle to move freely with minimum friction
 * Standard Bearing Sizes
 * Bearings use standard dimensions for inside diameter, width and outside diameter. standardized sizes include bearing bore size,bearing series, and external dimensions. note bearin brand and number when replacing crossover charts from one brand to another exist, but they are usually the same.
 * Sealed Front-Wheel-Drive Bearings
 * Wheel bearings that are sealed and do not have a grease fitting on them industry standard.
 * Bearing Greases
 * forms a film between the bearings and the races. Different types of greases are silicone, fluoether - based, labratory, and water soluble. Can handle high amounts of heat.
 * Seals
 * used to prevent liquids from leaking out of the part
 * · **Static Seals**- seals are used in all vehicles to keep lubricant from leaking out and to prevent dirt, dust, or water from getting into the bearing or lubricant. **Static seals** are used between two surfaces that do not move.
 * Dynamic Seals
 * used to seal between two surfaces that move
 * Symptoms and Diagnosis of Defective Bearings
 * Non-Drive Wheel Bearing Inspection and Service
 * Service
 * 1. hoist the vehicle safely
 * 2. remove the wheel
 * 3. remove the brake caliper assembly and support it with a coat hanger or other suitable hook to avoid allowing the caliper to hang by the brake hose.
 * 4. remove the grease cap
 * 5. remove the old cotter key and discard.
 * 6. remove the spindle nut
 * 7. remove washer and outer wheel bearing. remove the bearing hub from the spindle. the inner bearing will remain in the hub and may be removed after the grease seal is pried out.
 * 8. clean the bearing thoroughly in solvent.
 * 9. carefully inspect the bearing and the races for the following
 * the outer race for lines, scratches, or pits
 * the cage should be round. if the round cage has straight sections, this is an indication of an overtightened adjustment or a dropped cage.
 * Bearing Failure Analysis
 * Whenever a bearing is replaced, the old bearing must be inspected and the cause of the failure eliminated.
 * Metal Fatigue- Caused by long vehicle usage, even under normal conditions. Cracks appear and eventually they expand downward into the metal from the surface. Metal between cracks can chip off, this process is called spalling.
 * Electrical Arcing- Bearings can be damaged caused by poor ground wires or improper welding on the vehicle.
 * Shock Loading- Dents can be formed in the race of a bearing, which eventually leads to bearing failure.
 * Drum Brake PartsBacking PlateShoe AnchorsBrake Shoes
 * Duo Servo brake drum-
 * most common used
 * one anchor and a singe two piston wheel cylinder mounted at the top with the wheel cylinder directly below the ancor
 * - Primary and Secondary Non Servo - Leading / TraillingWheel CylinderReturn SpringsHold Down Pin/Spring and CapPark Brake CablePark Brake LeverAdjuster LeverAdjuster ScrewPark Brake Strut and Spring Duo Servo Drum Brakes
 * Leading-Trailing Drum Brakes
 * Advance Leading-Trailing Drum Brakes
 * Brake Drum Removal
 * Hubbed Drums
 * ** Hubbed drums have wheel bearings inside them **
 * Hubless Drums
 * a drum that does not contain bearing races
 * Drum Brake Disassembly and Inspection
 * Proper Lubricants
 * You should use silicone brake grease whenever dealing with brakes.
 * Minimum Lining Thickness
 * the lowest thickness the brake linings can be before they need to be replaced
 * Return Spring Inspection
 * check to make sure that the spring is not broken and is still tight
 * Hold down springs- Hold down springs keep the shoes securely against the support pads on the backing plate. The holddowns prevent noise, vibration, and wear, but still allow the shoes to move out and back as the brakes are applied and released. The holddowns also provide enough freedom of movement to allow adjustments of the shoes outward as the linings wear. The most common design is a steel pin installed through a hole in the backing plate and a corresponding hole in the brake shoe web. A spring fits over the end of the pin against the shoe web, and a special washer compresses the spring and locks onto the fattened end of the pin. Another type is a taper-wound coil spring with a hook formed on its end, and is sometimes called a beehive hilddown. The hook end of the spring is installed through a hole in the brake shoe web and attached into a retaining clip that fits into a corresponding hole in the backing plate.
 * Self-Adjusters
 * Wheel Cylinders (Parts ID)
 * Bearingized Surface: A finish inside the wheel cylinder to provide a smooth surface for the wheel cylinder seals and pistons to seal.
 * Reassembling Drum Brakes
 * 1. Carefully clean the backing plate.
 * 2. Check the anchor pin for looseness.
 * 3. Lubricate the shoe contact surfaces with antiseize, brake grease, or synthetic grease.
 * 4. Reassemble the primary and secondary shoes and brake strut, along with the springs.
 * 5. Finish assembling the drum brake, being careful to note the correct location of all springs.
 * Adjusting Drum Brakes
 * Most drum brakes are adjusted by rotating a starwheel or rotary adjuster. As th adjuster is moved, the brake shoe moves toward the drum. If the brakes have been assembled correctly and with the parking brake fully released, both brake shoes should make contact with the anchor pin.
 * Parking Brakes
 * when applied it locks up the rear wheels and on some cars the fronts as well. used for parking an hills or parking manual transmition cars.
 * Parking Brake Lamp
 * Parking Brake Cables
 * Parking Brake on Drum Brakes
 * Parking Brake Cable Adjustment
 * apply parking brake and count the number of clicks. it should be no more than 10 and no less than 4. if you need to make an adjustment then whip the car in neutral and relealse the parking brake, hoist car up, clean and adjust the rear brakes. reassemble the rear brakes and apply the parking brake 3-4 clicks. if the rear wheels still move then adjust the parking brake till the rear wheel brakes are just touching the brake the drums.
 * Disc Brake Operation and Parts
 * fluid from the master cylinder is forced into a caliper where it presses against a piston. the piston then squeezes 2 pads against the rotor. which is attached to the wheel, forcing it too slow down. parts of a disc brake include: the rotor, caliper, pads
 * Fixed Calipers
 * Earliest design. uses two, four, or six pistons to apply brake pads. gets its name from the fact that the caliper is rigidly mounted to the suspension. when brakes are applied, the pistons extend from the caliper base and apply the brake pads with equal force from both sides of the rotor. no part of the caliper body moves when brakes are applied.
 * Floating and Sliding Calipers
 * The caliper slides to engage the outside pad.
 * Low Drag Calipers
 * low drag calipers retract further than regulat calipers, and they also need a quick take up master cylinder
 * Brake Pad Wear Compensation
 * one pad econtacts first then the second one contacts and then the first lets go and then the second so as to get even wear out of the pads
 * Disc brake pads- A brake pad is a relatively simple part that consists of a block of friction material (made of a binder such as a thermosetting resin, fibers for reinforcement, and a friction modifier to obtain a desired coefficient of friction) attached to a stamped steel backing plate. Some manufacturers use tabs, or pins, and others use retainer springs to attach the pad to the caliper. As with brake shoes, the lining material of a disc pad can be any one of a number of products that can be fastened to the backing plate in several ways. Several methods that are used to mount brake linings include:
 * one pad econtacts first then the second one contacts and then the first lets go and then the second so as to get even wear out of the pads
 * Disc brake pads- A brake pad is a relatively simple part that consists of a block of friction material (made of a binder such as a thermosetting resin, fibers for reinforcement, and a friction modifier to obtain a desired coefficient of friction) attached to a stamped steel backing plate. Some manufacturers use tabs, or pins, and others use retainer springs to attach the pad to the caliper. As with brake shoes, the lining material of a disc pad can be any one of a number of products that can be fastened to the backing plate in several ways. Several methods that are used to mount brake linings include:
 * Wear Sensors
 * Electrical Brake Wear Indicators
 * Visual Inspection Even with operating wear indicating sensors a thorough visual inspection is very important. A thorough visual inspection can only be accomplished by removing the friction pads and checking for pad thickness and cracks.
 * Disc Brake Calipers-Removal and Inspection
 * Removal
 * 1. Hoist vehicle and remove wheels.
 * 2. Note the caliper mount position before removing caliper.
 * 3. Many manufacturers recommend removing one-half of the brake fluid from the master cylinder.
 * 4. Open bleeder valve to allow the old fluid to be forced into a container rather than the master cylinder.
 * 5. Remove retaining bolts (guide pins).
 * 6. If caliper is not being removed, it must be supported by a piece of wire so the rubber brake hose is not supporting the weight.
 * Inspection
 * Check for brake fluid in and around the piston boot area. If the boot is damaged or a fluid leak is visible then a caliper assembly repair or replacement is required.
 * Phenolic Caliper Pistons
 * Phenolic caliper pistons are made from phenol-formaldehyde resin compound combined with various reinforcing fibers. Its a natural thermal insulator which helps keep heat from transferring through the caliper piston to the brake fluid. They are lighter in weight and brown in color.
 * Steel Caliper Pistons
 * Steel pistons first plated with nickel then chome to achieve the desired finish
 * Reassembling disc Brake Calipers
 * Caliper Mounts
 * Test Drive After Repair
 * Bedding-in (Burnishing)Replacement Brake Pads
 * Correcting Disc Brake Squeal
 * can be caused by bad rotors, loose brake pads, lack of silicone compound on the back of the pad. to fix it, make sure rotors are true, brake pads are tight, and make sure the pads have enough silicone compound on the back of them
 * 2 types of rear disc brakes
 * parking brake design. 1. adapt the disc brake to also function as the parking brake using a series of cables, levers, and internal parts like actuating screws to mechanically move the caliper piston.
 * 2. use mechanically actuated drum brakes inside of the rear rotors. commonly found on trucks.
 * Rotating Pistons Back into the Caliper
 * This is on rear disc brake with intergrated parking brake, when putting the pistons back into the caliper you have to apply pressure while turning the piston, there is a special tool for this.
 * This is on rear disc brake with intergrated parking brake, when putting the pistons back into the caliper you have to apply pressure while turning the piston, there is a special tool for this.