Brake Faults
(1) Brake pedal goes to floor board without braking action.
(2) One or more brakes drag.
(3) Vehicle pulls to one side when braking.
(4) Poor braking effect requiring excessive pedal force.
(5) Soft or spongy pedal.
(6) Loss of brake fluid.
(7) Noisy brakes.
(8) Brakes grab or hard.
(9) Brake drums or discs heat up during driving.
(10) Brake pedal pulsation.
(1) Brake pedal goes to floor board without braking action.
Possible Causes :
1. Lack of brake fluid.
2. Brake shoes are out of adjustment.
3. Brake linings are worn out.
4. Air or vapor in the hydraulic system.
5. Wheel cylinder pistons are seized.
6. Worn out or defective master pump.
7. Leak past primary cup in master pump.
(2) One or more brakes drag.
Possible Causes :
1. Clogged brake line.
2. Shoes or pads are stuck with drums or discs due to corrosion.
3. Shoes out of adjustment.
4. Wheel cylinders defective.
5. Weak or broken shoe return springs.
6. Loose wheel bearings.
7. Defective master pump.
(3) Vehicle pulls to one side when braking.
Possible Causes :
1. Brake linings are soaked with oil, grease or brake fluid.
2. Brake shoes are out of adjustment
3. Brakes dragging on one side.
4. Defective wheel cylinder.
5. Clogged brake lines.
6. Brake back plate is loose.
7. Linings are mismatched(Having different friction coefficients)
8. Uneven tire pressure or tiers worn out.
9. Incorrect wheel alignment (caster or camber angle)
10. Tight wheel bearing.
11. Uneven or broken springs.
12. Uneven torsion bar adjustments.
(4) Poor braking effect requiring excessive pedal force.
Possible Causes :
1. Brake drums or discs are glazed.
2. Brake linings or pads are burnt or very hot.
3. Brake shoes or pads are soaked with water, oil, grease or brake fluid.
4. Brake shoes are out of adjustment.
5. Power assisted brake unit not operating.
(5) Soft or spongy pedal.
Possible Causes :
1. Brake shoes out of adjustment.
2. Air or vapor in the hydraulic system. Air or vapor can enter into the system by,
(a) Leaky master cylinder check valve which does not maintain a slight pressure in the system.
(b) Brake fluid leaks through wheel cylinder cups.
(c) Insufficient brake fluid in the master cylinder
(d) Damaged brake pipes.
(e) Loose brake pipe connections.
(6) Loss of brake fluid.
Possible Causes :
1. Leaks through wheel cylinder cups.
2. Brake actuating pins are cocked causing side thrust on pistons and leaks through piston cups.
3. Brake line is damaged or leaks through brake pipe connections.
4. Bleed screw is open or partly closed.
5. Maser cylinder leaks.
(7) Noisy brakes.
Possible Causes :
1. Brake liners are worn and rivets scrape the drum.
2. Loose rivets touch the drum.
3. Brake pads are worn out and the wear indicator touches the drum.
4. Shoes are warped and do not contact with the drum properly.
6. Drum surface is not uniform and partly contact with shoes.
7. Loose back plate or linkages.
5. Liners are oil wet, burnt or lost properties.
(8) Brakes grab or hard.
Possible Causes :
1. Brake shoes are out of adjustment.
2. Brake drums are scored or rough.
3. Loose back plate.
4. Defective brake booster.
(9) Brake drums or discs heat up during driving.
Possible Causes :
1. Seized wheel cylinder piston.
2. Sticking pedal linkages.
3. Incorrect pedal linkage adjustment.
4. Power booster unit is defective and seized.
5. Continuous use of brakes.
6. Master cylinder residual check valve not released.
(10) Brake pedal pulsation.
Possible Causes :
1. Brake drum with uneven surface.
2. Brake disc thickness uneven.
3. Brake disc rotation out of parallel.
4. Loose wheel bearing.
5. During ABS actuation.