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What are the symptoms of a defective master cylinder?


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2010-11-20 02:28:48
2010-11-20 02:28:48

usually they will leak out the back by the booster, your brake pedal will slowly go to the floor at stops or the brake pedal will go right to the floor when pushed.

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Related Questions

Master cylinder empty (no brake fluid) Leak in brake line or wheel cylinder Defective master cylinder

A symptom you almost always feel is a brake pedal that will not hold. You stop, hold the brake, and the pedal will slowly move toward the floor. This is a sure sign the master cylinder is bad. A leaking master cylinder or one that sticks, is also a sign is is defective. When you replace the master cylinder replace all the brake fluid in the brake system and bleed the brakes. Moisture in the brake fluid will destroy a master cylinder and this may be why it failed.Brake fluid leaking from the master cylinder. When you stop and hold your foot on the break the brake pedal will slowly go to the floor. Either of these symptoms means your master cylinder must be replaced.

The most common symptom of a master cylinder that has failed is that when you stop and hold your foot on the brake pedal it will slowly fall to the floor. This is called pedal fade and means the seals within the master cylinder are leaking. If you push the brake pedal and it does not return it may be defective. You may also see a leak at the master cylinder.

If the Master Cylinder is defective then replace it.

Master cylinder is defective. Replace it.

Logically if the Master Cylinder keeps failing there are only a certain amount of things coming into play here. Either you are buying defective products or the brake fluid is contaminated and causing the Master Cylinder to fail prematurely. Let's start with the Master Cylinders you are installing. I will not name suppliers but not all Master Cylinders are created equal. Some rebuilt Master Cylinders are defective right out of the box. I suggest you buy a NEW master cylinder. Before installing the new Master Cylinder flush all old brake fluid out of the entire system, install a new master cylinder and install fresh fluid from an unopened can. With a new master cylinder and fresh clean fluid, you should have no future problems.

Low fluid level or defective master cylinder.

I would suspect a defective Master Cylinder. Fluid leak.

Defective master cylinder, low of fluid, or leak somewhere else in the system.

There is still no fluid pressure. Make sure that the master cylinder was bled as well as the wheel cylinders. New master cylinders can be tough to bleed all of the air out. The new master could be defective.

Well if you continue to drive it with a defective master cylinder, your brakes will eventually fail, and you can end up having a wreck and possibly killing yourself or someone else. Is that enough damage for you? Replace the master cylinder and don't be an idiot.

Contaminated brake fluid? Frozen calipers? Defective master cylinder? Master cylinder activation rod not adjusted properly?

Defective master cylinder? Frozen caliper? Parking brake cable frozen?

Air in the brake hydraulic system or defective master cylinder.

Defective Master Cylinder or broken brake line. Replace the master cylinder and bleed the brakes.

Start the engine. Place you foot on the brake pedal, and press fairly hard and hold the pedal down. If the pedal very slowly, moves toward the floor any at all, the master cylinder is defective. Replace it immediately!!!!!

Master Cylinder seals are defective. Replace the Master Cylinder ASAP. Stop driving the vehicle until you have this repaired. The brakes can fail completely at any moment.

the pedal will slowly depress with no loss of fluid

By repairing the problem. Low brake fluid, defective master cylinder, etc.

Get someone to help you and bleed the brakes again. You should have bench bled the master cylinder before installing. Start at the right rear, then go to the left rear, right front, and end at the left front brake. Bleed each caliber until you see no more air escaping. If you do not know how to bleed your brakes a Google search will give you instructions. If you do it right, assuming the Master Cylinder is good, you will have good brakes. I have seen rebuilt master cylinders that were defective out of the box. If you bought a rebuilt master cylinder, I would recommend you return it and get a new master cylinder. Rebuilt products today are not rebuilt in the U.S. and it is common for them to be defective. Buy new!

If sitting still in your car with the engine running you can apply the brakes and the pedal slowly goes towards the floor you have a defective brake master cylinder. The only repair is to replace the master cylinder. This is a very dangerous situation and must be repaired immediately. Failure to replace the master cylinder may result in an accident.

a heater does not have a master cylinder; 'master cylinder' goes with assisted braking.

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