What is the reason why the brakes become very low when the brakes are applied after the car is repla

Hello、It's likely that the brake stroke changes、And the brake fluid。

Caused by too low、I hope it will help you、Hope、Thank you。

Hello, you may not have completely emptied the air inside, it is recommended that you try again after emptying the air, I hope mine can help you, thank you.

The role of automobile brake cylinder:

1. After pressing the brake, the main cylinder causes thrust to press the hydraulic oil to the sub-cylinder, and the piston inside the sub-cylinder begins to move under hydraulic pressure to push the brake pads;

2. The oil brake is composed of a brake master cylinder and a brake oil storage tank. They have the brake pedal attached to one end and the brake hose to the other. The brake master cylinder is stored with brake fluid, and there are oil outlets and oil inlets. When the brake is applied, the oil outlet is open and the oil inlet is closed;

3. Under the pressure of the piston of the pump body, the brake oil pipe is squeezed out of the oil pipe and flows to each brake cylinder for braking function. When the brake plate is released. The oil outlet in the brake master cylinder will be closed and the oil inlet will be opened, so that the brake oil will flow back from each brake cylinder to the brake master cylinder and return to the original state.

Hello, this just loosen the lock nut of the master cylinder pusher and twist the pusher by changing its length so that the gap between it and the piston changes, and change the free stroke, look.

As long as there are brakes, this is not a problem, in this case, when the brake master cylinder is installed, the free stroke is reduced.

The reasons may be: there is air in the pipeline, free travel of the pedal or the brake clearance is too large, if the brake is soft, it is recommended to go to the 4S shop to check the specific reason, brake to drain the air, it is best to use a computer detector to discharge the brake air.

Brakes

What happens when a car is able to drive on the road because of the wheels, but when the car is about to stop? The driver can't put his feet on the ground to stop the car from moving forward like in the cartoon, so he has to rely on the brakes on the car to reduce the speed of the car and stop it.

The braking device creates friction between the brake pads and the wheel drum or disc, and in the process of friction, the kinetic energy of the car is converted into heat energy and dissipated. There are two types of common brake devices: "drum brake" and "disc brake", and their basic characteristics are as follows:

Brake classification. Drum brakes.

Two semi-circular brake pads are installed in the wheel hub, and the brake pads are pushed by the "lever principle" to cause friction between the brake pads and the inner surface of the wheel drum.

Mode of action of drum brakes.

To put it simply, drum brakes are brake devices that use the static brake pads in the brake drum to rub the brake drum that rotates with the wheels to generate friction and reduce the rotation speed of the wheels.

When the brake pedal is pressed, the force applied by the foot causes the piston in the brake master cylinder to push the brake fluid forward and create pressure in the oil circuit. The pressure is transmitted to the piston of the brake cylinder of each wheel through the brake oil, and the piston of the brake cylinder pushes the brake pad outward, so that the brake pad rubs against the inner surface of the brake drum, and produces enough friction to reduce the speed of the wheel, so as to achieve the purpose of braking.

Advantages of drum type. 1.There is automatic braking, which allows the braking system to use lower oil pressure, or to use a brake drum with a much smaller diameter than the brake disc.

2.The installation of the hand brake mechanism is easy. Some models with disc brakes on the rear wheels will install a hand brake mechanism with drum brakes in the center of the brake disc.

3.The processing and composition of parts are relatively simple, and there are relatively low manufacturing costs.

There are the following reasons:1. Brake oil pipe leakage or air intake.

If the brake oil performance is not good, the friction between the brake pad and the brake disc is not sufficient, and the driving time is long, the brake oil pipe may be aging and damaged, resulting in brake oil leakage or air entering the oil circuit, and there is an air barrier between the brake pad and the brake disc, which will cause the brake to become soft, and the oil pipe needs to be replaced to remove the air.

2. The brake fluid has not been replaced for a long time.

If the brake fluid is not replaced in time, it will contain too much hybrids and moisture inside, which will affect the transmission of braking force. Therefore, the brake fluid must be replaced regularly, and if possible, it is necessary to go to a professional repair shop to test the moisture content of the brake fluid, and replace it when necessary.

3. The new brake pads are not running-in.

The surface of the brake pad just changed is relatively flat, and the contact surface with the brake disc is small, and the braking force will be relatively low, which also causes the situation that the brake cannot be stopped. Replace the new brake pads, are required to go through a period of running-in, generally need to run in about 200 kilometers, only after the running-in period, in order to achieve the best braking effect.

Hello, if the air inside is not discharged clean when it is installed, this situation will occur It is recommended to change the brake oil for a few days to exhaust the air It is not excluded that the master cylinder is like that [If the car has a problem, ask the car master. 4S shop professional technician, 10 minutes to solve. 】

The brakes become softer and lower.

The reason could be that there are air bubbles in the brake fluid.

In the parked state, the engine can be started and neutral can be hung up.

Then apply the brakes firmly for more than 2 minutes and repeat 3 times.

Doing so might get rid of some of the bubbles.

If it still doesn't work, it is recommended to replace the brake fluid.

In general, in this case, first exhausting the air and then adjusting the four brake clearances down will generally solve the problem.

This situation also has a lot to do with the condition of the car, if it still doesn't work, it is recommended to go to a professional auto repair shop to overhaul, so as not to affect the driving.

I hope the above is helpful to you and I wish you a pleasant ride

During repair, the system intakes, or the first oil leakage, the gap between the disc and the disc or between the disc and the drum is large, the new piece is not run in well, the master cylinder is faulty, the brake disc is thin, etc., will cause the phenomenon of softening and lowering.

Do you see if the above includes your question? For example, the brake disc is thin, not running in well, and the gap adjustment is not suitable,......

It should be that there is air in the brake fluid. Check whether there is air in the brake oil circuit, you must hit the car, press the brake pedal, feel what it looks like when you step on it for the first time, and then continue to pedal if there is no change from the first time to prove that there is no air, if you step on it harder and harder to prove that there is air, you must continue to exhaust.

Hydraulic brake exhaust method: due to the air in the brake oil, the compression of the air makes the brake pump can not return well, and the brake pad and the brake disc can not be completely separated, resulting in the "squeak, squeak" sound of the front brake.

Introduction:

The brake cylinder is an indispensable chassis brake part of the braking system, and its main role is to push the brake pads and the brake pads to rub the brake drum. Reduces the speed of the vehicle and makes it stationary. After the brake is pressed, the master cylinder generates a thrust to press the hydraulic oil to the cylinder, and the piston inside the cylinder begins to move under hydraulic pressure to push the brake pads.

Hydraulic brakes are made up of a brake master cylinder and a brake fluid reservoir. They have the brake pedal attached to one end and the brake hose to the other. The brake master cylinder is stored with brake fluid, and there are oil outlets and oil inlets.

The problem reflected by the master in the technical aspect to check whether the gas in the brake cylinder has been discharged after replacing the brake oil, if the gas is not discharged and the braking effect is not good, the brake pad should be adjusted to death first, the wheel rotates freely, there is no hairpin phenomenon after stepping on the brake for a number of times, the newly replaced brake pad needs a certain run-in period, step on the brake more in the driving, force the run-in, and return to the original state after a periodic run-in. There is also an impact on the braking performance is the quality of the brake pads, some manufacturers in order to save costs in the material to do tricks, resulting in hard brakes, poor performance, so it is necessary to replace the original brake pads.

Occasional brake failure can be caused by a variety of causes, such as brake fluid (brake fluid), oil pipes, brake pumps, brake pads, brake drums or discs, vehicle weight, driving routes, and weather conditions. Brake fluid is an important part of the braking system, and the worst is directly related to whether the braking is reliable. The brake fluid should be checked frequently, and the same type of brake fluid should be replenished if it is missing, and it should be replaced once every three years.

Don't change the brake pads and brake discs at the same time, the front and rear wheels should be separated by half a year, and then change to another one.

Brake a few more times, and wait for the piece to grind out.

1. The oil quality is too dirty, which leads to the blockage of the brake oil pipe and causes the pressure of the master pump to be too large, and the brake is ineffective and the oil pump is easy to be damaged after a long time.

2. The oil quality is too low or the time is too long to deteriorate, and the sealing bowl in the main pump is easy to corrode, which will cause poor sealing after a long time, and it will not be able to seal the oil without oil pressure.

3. Frequent lack of oil or dry grinding will cause wear and tear of leather bowls.

4. Frequent use of brakes will also be unfavorable to brakes.

Hello, this is possible, I hope I can help you, if you don't understand, you can continue to ask me! Have a great day! [If you have a big problem with the car banquet, ask the car master. 4S shop professional technical salesman, 10 minutes erection bell solution. 】

Hello, it may cause the brake master cylinder to rust to death. [If you have a problem with the car, ask the car master.] 4S shop professional technician, 10 minutes to solve. 】