Brake Failure

Brake Failure: Top 14 Causes & Remedies


What is Brake Fade?

Brake failure includes the phenomenon called Brake Fade that takes place due to the reduction of braking performance. This is because of the building-up of heat at the disc or drums of the brakes. Typically, Brake Fade occurs due to rough use of brakes (i.e. pressing them hard and repeatedly) during a short duration. To reduce this “Fade” problem, you need good ventilation for the brake. That’s why a large number of vehicles use ventilated disc brakes on the front wheels. Brake fade usually occurs to recently developed performance cars due to aggressive driving.

Why Does It Occur?

Furthermore, brake fade can be a factor in brake failure that comprises of a friction braking system. That ultimately includes almost every vehicle per se such as cars, trucks, motorcycles, and bikes. Brake fade can either be mechanical fade, friction fade, or fluid fade. It usually occurs during high-performance drives or during a steep descent.

Remedy:

However, it is more common in drum brakes than discs due to its construction. It can be reduced significantly by using correct methods and materials, design and selection, as well as thru’ proper cooling. You can reduce the brake failure such as Brake fade and rotor wrapping. You can do it through proper braking techniques such as applying brakes on a long slope at lower gears. However, for automatic transmissions, the driver may need a brief use of the throttle after selecting the gear. 

What is Brake Judder?

Furthermore, vibrations felt during braking that is caused by a distorted disc, out of shape drums, or worn out pads. Judder is easily noticeable when braking from high speed. However, if present, it should be attended to immediately.

Following are some of the possible causes and remedies for brake failure

Sr. No. Trouble Cause Remedy
1. The brake pedal is soft and spongy. a. The air in brake system. a. Bleed the brake system.
  b. Brake fluid too hot (after long time operation of the brake) b. Give the brake system time to cool down and if necessary, and bleed
  c. One of both primary seals in the tandem master cylinder damaged. c. Replace primary seals.
  d. Brake shoes are worn out. d. Replace shoes.
2. Unsatisfactory braking action despite hard pedal pressure (normal pedal travel) a. Brake shoes oily or greasy. a. Rectify the cause of leakage and clean brake drum/disc.
  b. Brake shoe/pads charred. b. Replace the parts.
  c. Brake shoes/pads worn. c. Replace.
  d. Vacuum booster defective d. Rectify/Replace.
  e. Brake shoe/drum distorted. e. Check and rectify.
3. Brakes heat up when the vehicle is traveling or fail to release. a. Compensation port in tandem master cylinder clogged. a. Dis-assemble the tandem master cylinder and clean.
  b. Rubber parts were swollen because of the usage of non-recommended fluids. b. Drain the brake system and dismantle the whole brake system. Replace all rubber parts including the brake hoses. Fill brake system with one of the approved brake fluids.
  c. Brake drum shoe clearance is morec. Adjust.
  d. Brake shoe return-spring weak/broken. d. Replace
  e. Brake drum out of true of scorede. Rectify.
  f. Anchor plate/caliper mountingf. Tighten bolts.
  g. Slack hub bearing. loose. g. Rectify.
  h. Vacuum booster piston seized. h. Rectify/replace.
  i. Weak/broken pedal return spring. i. pivot and linkage. Brake Failure: Replace spring lubricate

Brake Failure: Troubleshooting Tips:

4. Unsatisfactory braking action despite hard pedal pressure leaky. (short pedal travel) a. Vacuum hose or connections leaky. a. Eliminate leaks.
  b. Damaged vacuum seal in tandem master cylinderb. Replace vacuum seals.
  c. Damaged O-ring between the tandem master cylinder and vacuum booster. c. Damaged O-ring
  d. Damaged seal on vacuum booster piston. d. Replace vacuum booster.
  e. There is a tear in the diaphragm. e. Replace vacuum booster.
  f. Check valve sticking. f. Replace the vacuum line together with the check valve.
  g. A defective vacuum pump. g. Repair the vacuum pump.
5. Unsatisfactory braking action despite hard pedal pressure excessive. (long pedal travel) a. excessive drum to shoe clearancea. Adjust brakes.
  b. Incorrect brake fluid. b. Incorrect brake fluid. b. Flush the system and use specified brake fluid.
  c. Cracked drums. c. Replace brake drum.
  d. Excessive wear in brake pedal linkage. d. Inspect and rectify linkages.
  e. Wheel bearing play is excessive. e. Adjust.
  f. Mounting of brake part loose/defective. f. Rectify and tighten.
  g. One brake circuit inoperative through leaks. g. Eliminate leaks.
6. Brakes dragging on one sidea. Brake shoes/pads oily or greasy. a. Check seals of the wheel hub, replace brake pads/shoes.
  b. Brake shoes/pads of one side excessively worn. b. Replace brake shoes/pads.
  c. There is a difference in friction valve of brake shoes/pads. c. Replace brake shoes/pads.
  d. Out of round drums. d. Correct by grinding/turning.
  e. Bad tires. e. Replace worn tires.
  f. Brake anchor plate/caliper mounting loose. f. Tighten firmly.
     

Brake Failure: Troubleshooting Tips:

7. Brakes squeaking or Judder. a. Brake drum out of round. a. Check and rectify.
  b. Brake drum/disc out of true. b. Check and rectify.
  c. Brake linkages having high frictionc. Check and rectify.
  d. Brake liners not chamfered. d. Check and rectify.
  e. An excessive air gap between liners and shoe. e. Check and rectify.
  f. Loose brake liner rivets. f. Check and rectify.
  g. Anchor plate/caliper brake mounting loose. g. Tighten.
  h. Lining/pad worn out excessively. h. Check and rectify.
  i. The wheel bearing play is not in order. i. Adjust it.
8. Rattling brakes. a. Unsatisfactory wear pattern of brake shoes. a. Properly run-in brake shoes.
  b. Check shock absorbers. b. Adjust or replace if necessary
9. The fluid reservoir needs frequent topping up. a. Leak in hydraulic unions for leaks. a. Check all liners, hoses, and unions for leaks.
  b. Brake fluid escaping from leak port of tandem master cylinder. b. Replace vacuum seals in leak port of tandem master cylinder. If necessary, remove brake fluid from the vacuum booster.
10. Sudden braking effect inspite of light pedal pressure. a. Brake incorrectly adjusteda. Readjust brake.
  b. Brake anchor plate/caliper mounting loose. b. Firmly tighten anchor plate.

Brake Failure: Troubleshooting Tips:

11. Uneven wear on brake lininga. Check for the correct type of brake material lining materialsa. Fit approved makes only.
  b. Wheel cylinders corroded. b. Clean/repair the cylinders.
12. Pistons seized in wheel cylinders. a. Shoe assembly linkages dirty or corroded. a. Check, rectify and free cylinders.
  b. Mounting of wheel cylinder out of line or loose. b. Check and rectify.
  c. Corrosion of cylinder bores. c. Remove corrosion/rectify.
13. Parking brake ineffective. a. Change brake shoe after leakage if any. a. Change brake shoe after rectifying the cause of leakage if any.
  b. Excessive clearance between brake lining and drum. b. Adjust brake shoe to drum clearance.
  c. The excessive free play of cables. c. Adjust cables.
14. Poor brake / Rear-wheel lockinga. ‘G’ conscious valve not functioninga. Replace
  b. LCRV not functioning b. LCRV Adjust the gap. If the problem is not solved replace it.

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