What is the reason for the lack of braking force and the weakening of braking efficiency?

Brake pads are badly worn.

Braking properties of motor refers to the ability of a car to force a car to slow down and even stop while driving, or to maintain a certain speed when going downhill. The braking process of a car is carried out with the help of wheel brakes, engines or specialized auxiliary brakes that artificially increase the driving resistance of the car.

When braking, the tangential reaction force (i.e., braking force) on the wheels of the road opposite to the direction of the car is generated by the interaction between the braking wheels (usually the front and rear wheels of the car are brake wheels) and the road surface, which has a decisive impact on the braking performance of the car, and its maximum value depends on the adhesion between the tire and the road surface. The evaluation indicators of braking performance are: braking deceleration, braking time and braking distance.

The braking performance of a car depends on the braking system design and tuning. The key to ensure the constant braking performance is to adjust the clearance appropriately, the ratio of the left and right wheels and the proportion of the front and rear axles are coordinated, and the friction material with strong thermal decay resistance is used. In China's product finalization test, there are strict procedures for braking distance, deceleration, thermal decay resistance of braking system and emergency braking at various initial speeds, and it should be considered that the brakes used in the models that have passed the national finalization test procedures are reliable, or the brake structure and material design are reasonable.

Of course, the adjustment in the assembly process is an important factor that causes the failure of the brake system to affect the driving, and the abnormality of individual parts in the manufacturing process is also the main factor causing the driving brake failure. Including braking distance and braking deceleration, these two indicators are essentially the same. It is specified in GB7258-97:

When the car meets the braking distance requirements or braking deceleration requirements, the braking performance is considered to be qualified, and the initial braking speed of M1 vehicles is changed from the original 30km h to 50km h, and the braking deceleration is changed from the original average deceleration to the average deceleration fully issued. Obviously, the speed limit for M1 vehicles with a speed of more than 150 km/h is low.

The normal working temperature of the water-cooled engine should be 80-90 degrees. The temperature of the engine is taken as an example of the Jiefang CA10B car, and according to the temperature of the engine, the shutter joystick in the cab can be pulled out (i.e., opened) or pushed out (i.e., opened and closed) to change the amount of air entering the radiator, so as to adjust the engine temperature.

1. The braking force of the car itself is not good;

2. The brake fluid of the car is insufficient;

3. The brake pads are too thin;

4. The pattern of the tire is gone;

5. The speed is too fast and the inertia is too large.

Some of them are because of pedal problems!

Insufficient braking force, there may be air resistance in the oil pipe, it is recommended that you remove the air, check whether the brake pads are seriously worn, if there are problems, it may be caused by the main cylinder pressure relief or the sub-cylinder is not good.

Loose pipe joints or cracked pipes, air leaks, or oil leaks. The brake shoe pad and the brake clearance are improperly adjusted, and the hoof is filled with oil or mud and water.

It should be that the brake pads are too badly worn, resulting in poor performance.

The active reason for the weakening of braking ability is due to other performance degradation.

What is the reason for the lack of braking force and the weakening of braking efficiency?

The main reason for the weakening of braking effectiveness is a problem with the brake pads.

The reason for the reduced efficiency may be due to brake loss.

There are many reasons for the weakening, and handbrake aging is also one.

There are many reasons for the weakening, such as a problem with the handbrake.

Prolonged use of the brakes leads to severe wear.

Causes of insufficient braking force of automobiles:

1. The pressure of the brake oil of the oil brake (oil brake vehicle) is insufficient. (lack of oil in the brake master cylinder, rupture of the brake line, leakage of the oil pipe joint, and blockage of the oil line);

2. There is air in the braking system of oil brake (oil brake vehicle);

3. Insufficient air pressure for air brake (air brake vehicle). (The compressor gas supply is insufficient, and the brake chamber, air storage tank, and brake pipeline are leaking);

4. The free stroke of the brake pedal or the gap of the brake is too large, the brake shoe is called early, the friction plate is not in good contact or the pedal return spring is soft, and the wear is serious or there is oil stain;

5. The brake master cylinder, wheel cylinder piston and cylinder tube are worn or strained, and the leather bowl is old and damaged.

Solution: Eliminate the fault according to the lack of braking force of the automotive hydraulic braking system.

1) Insufficient brake fluid. Replenish the brake fluid.

2) The brake pedal is too large. Adjust the pedal free stroke.

3) If there is a blockage or oil leakage in the braking system, dredge the pipeline or repair the leakage part.

Hello Insufficient braking force of the car Failure Cause:

1. The pressure of the brake oil of the oil brake (oil brake vehicle) is insufficient. (lack of oil in the main cylinder of the buried brake, rupture of the brake pipeline, leakage of the oil pipe joint, and rough plugging of the oil circuit);

2. There is air in the braking system of oil brake (oil brake vehicle);

3. Insufficient air pressure for air brake (air brake vehicle). (The compressor gas supply is insufficient, and the brake chamber, air storage tank, and brake pipeline are leaking);

4. The free stroke of the brake pedal or the gap of the brake is too large, the friction plate of the brake shoe is not in good contact or the pedal return spring is soft, and the wear is serious or there is oil stain; No town.

5. The brake master cylinder, wheel cylinder piston and cylinder tube are worn or strained.

If the braking force of the car is insufficient, you can check the braking system.

First, the brake fluid has not been changed for a long time

Brake fluid, also known as brake fluid, is a functional fluid that has an expiration date, just like engine oil.

Generally speaking, it is necessary to change the brake fluid once every two years, because some moisture and air will enter the brake fluid for a long time, which will reduce the boiling point of the brake oil, and reduce the braking performance due to the increase in oil temperature during emergency braking. Different brands of brake fluid may react when mixed, generating impurities and air, which can affect the braking force.

Second, the brake fluid enters the moisture and air

This sounds the same as the first case, but it's not. The first is the natural deterioration of the brake fluid, while the second is the introduction of moisture and air into the brake fluid due to human error or a harsh environment. Otherwise, after a long time, a large amount of water vapor will enter the brake fluid, which will seriously affect the physical properties of the brake fluid, and the consequences will be unimaginable when braking suddenly.

3. The pumping performance of the vacuum booster pump is weakened

Now, with the popularity of technologies such as direct injection and turbocharging, most cars are equipped with independent vacuum booster pumps to pump air from the vacuum booster to create a vacuum. But sometimes when the engine is under heavy load, such as when the air conditioner is turned on in the summer, the pumping strength of the engine will be weakened. This creates a situation where the vacuum level in the vacuum pump is insufficient.

When you brake continuously, the braking force of the first foot is sufficient, and the braking force of the second and third feet will decay.

Fourth, the brake master cylinder or sub-cylinder has oil leakage

If there is an oil leak in the main cylinder and the sub-cylinder, it will cause the pressure of the master cylinder to drop and weaken the braking force. Therefore, we also pay attention to the maintenance of the brake system on a daily basis to ensure the tightness and purity of the brake cylinder. It is recommended that when replacing the brake pads or brake discs, check whether the return of the brake cylinder is normal.

Troubleshooting:If the brake pedal is pressed continuously, if the pedal is gradually raised and there is a feeling of springing, but it is still very low when you press the pedal after stopping for a while, it means that there is air in the braking system, and the braking system should be exhausted.

One foot brake is not effective, but the braking effect is very good when pressing the pedal several times in a row, generally because the free travel of the brake pedal is too large or the brake clearance is too large. The free travel of the pedal should be adjusted, and then the brake clearance should be checked, and the brake disassembly repair should be carried out if necessary.

When the brake pedal is pressed, it is not soft or sinking, but the braking effect is poor, which is the fault of the wheel brake, such as the brake shoe with oil or poor contact, the aging and wear of the friction pad, and the uneven wear of the brake drum. The condition of the braking technology should be checked and adjusted and repaired if necessary.

When braking is needed in the driving process, the braking force is obviously insufficient, the brake pedal position is low or the idle stroke of the brake pedal is large during braking, the braking effect is still poor after continuous multi-foot braking during braking, and the braking distance and braking time are significantly increased during emergency braking. The cause of the failure may be the poor sealing of the brake sealing element or the loose fit between the piston and the cylinder wall of the brake cylinder, the bubbles mixed in the brake oil circuit, the poor contact of the brake element or the oil stain of the brake pad.

The braking performance of a car is related to the structure of the car and the conditions of use. Such as the distribution of the load between the axles of the car, the load weight, the structure of the braking system, the use of engine braking, the driving speed, the road conditions, the driving method, etc., all have a great impact on the braking process of the car.

Directional stability during brakingDirectional stability during braking refers to the ability of the car to drive in the direction given by the driver during braking, that is, whether there will be braking deviation (the car deviates when braking, but the rear wheels move along the trajectory of the front wheels), side slip (when braking, the car slides laterally on one or both axles, and the trajectory of the front and rear wheels is not heavy) or loses the ability to steer (if the front wheels lock and drag, the car will lose its steering ability).

The braking performance of the car is mainly due to abnormal air pressure:

The air pressure inside the air compression system is insufficient. When the air compressor does not work normally, the gas furnace is blocked, etc., when the car needs to brake, the compressed air pressure of the braking system is insufficient, and the normal braking performance may not be able to be played.

Reduced brake friction torque The spacing between the brake drum and the brake shoe of the braking system is not suitable. Insufficient direct contact area of brake shoes; Impurities such as deterioration in the quality of brake shoes or oil contamination; The brake shoe rivets are loose. Brake drum twisting can lose its roundness or create grooves.

Brake bearings, axles, sleeves, and other parts are rusty or severely worn and loose.

The reasons for the lack of braking force are as follows:

1. The brake oil pressure is insufficient. The brake master cylinder lacks oil, the brake pipeline is ruptured, the oil pipe joint is leaking, and the oil circuit is blocked; There is air in the braking system;

2. The air pressure of the vehicle is insufficient. (The compressor gas supply is insufficient, and the brake chamber, air storage tank, and brake pipeline are leaking);

3. The free stroke of the brake pedal or the brake clearance is too late, the brake shoe friction plate is not in good contact or the pedal return spring is soft, and the wear is serious or there is oil stain;

4. The main cylinder, wheel cylinder piston and cylinder tube are worn or strained, and the leather bowl is aged and damaged.

Hope it helps, hope, thank you!

The air pressure is insufficient (pneumatic type), and the oil level of the oil reservoir is too low (hydraulic type). The pedal free travel is too large.

The control valve touch piece is cracked or dented (pneumatic type), and the piston leather bowl of the main cylinder is leaking (hydraulic type Xun Pai wide). The brake chamber may be damaged.

Bad (pneumatic type), oil leakage from the piston leather bowl of the wheel cylinder (hydraulic type). Poor sealing of the exhaust valve of the control valve (pneumatic type). Pipe.

Loose joints or cracked pipes, air leaks, or oil leaks. The brake shoe and the brake gap are improperly adjusted, and the hoof skin is bright and occupies oil, oil or muddy water.

The oil pressure of the brake stove is insufficient, the brake master cylinder is short of oil, the brake pipeline is broken, the oil pipe joint is leaking, the oil circuit is blocked, the brake pedal is free to travel in the middle range or the brake clearance is too large, and the brake shoe Mose friction blade is in poor contact, and the wear is serious or greasy.

Generally, the lack of braking force is caused by the wear of brake pads, Yan Xiaochan and the lack of oil in the brake car, and the braking efficiency is low, which is a safety hidden danger, and the brake pads must be replaced or the brake fluid must be supplemented.

Hello The common faults of the car braking system are brake failure, brake deviation and brake failure. These three types of faults can damage the vehicle at least and affect driving safety, so they need to be dealt with as soon as possible.

1.Fault phenomenon: press the brake pedal, the pedal is not raised, and there is no resistance.

Determine the reason: check whether the brake fluid is missing; Whether there is oil leakage at the brake cylinder, pipeline and joint; Whether the parts of the main pump and sub-pump are damaged.

2.Fault phenomenon: the brake pedal is pressed to the end, and the braking effect is not good; Continuous braking, the effect does not improve, and the pedal gradually rises.

Reason: Gas is mixed in the braking system.

3.Fault phenomenon: continuous braking, pedal return is raised, and the braking effect is improved.

Judgment reason: The gap between the wiping pad and the brake drum is too large.

4.Fault phenomenon: continuous braking, the pedal position is raised, and there is a sinking feeling. Determine the cause: oil leakage.

5.Fault phenomenon: the pedal position is very low; If you step on it again, the position cannot be raised, and it feels hard.

Determine the cause: the main pump is blocked.

6.Fault phenomenon: The pedal height is normal, not soft or sinking, but the braking effect is not good.

Determine the reason: the gap between the friction pad and the brake drum is too large or there is oil stain.

7.Fault phenomenon: brake mistracking.

Determine the reason: if the car deviates to the left, the brake of the right wheel is ineffective, and vice versa.

8.Fault phenomenon: the car travels for a period of mileage, and the brake drum (disc) heats up.

Determine the reason: Check the brake master cylinder, brake cylinder or pipeline.

9.Fault phenomenon: The free stroke of the brake pedal is too small. Solution: Adjustments are required.

10.Fault phenomenon: the brake fluid level rises slowly.

Solution: Loosen the deflating screw and observe the return of the brake shoe. If the brake shoe returns, the oil pipe should be dredged; If the brake shoe does not return, the brake cylinder should be disassembled and checked.