Why Brakes Still Spongy After Bleeding? (Explained)

Brakes are an important component in the process of driving a car. It has an effect on the movement of the vehicle; if the brake is unstable, it is difficult to use and quite dangerous. Even minor errors on it can have a significant impact on your life.

It is not uncommon for the brake to remain spongy after bleeding. This is not a situation you want to be in, but it does happen from time to time.

I believe you will be irritated because the brake remains spongy after bleeding. However, we have a solution to this problem.

Even if you have never encountered a similar case, knowing a useful piece of information is not completely useless.

This article will explain why your brakes are still spongy after bleeding them. Furthermore, we provide the most useful fixes for this situation. Please read and apply if you come across this unusual case.

Reasons Why Brakes Still Spongy After Bleeding?

There are a few reasons that lead to brakes still spongy after bleeding. They happen all the time, but I don’t think you care. So pay attention to the following reasons.

1. Unproductive Brake Bleeding 

The most prevalent explanation is that your vehicle’s bleeding procedure has been inefficient.

Bleeding is often the only method to fix a soft brake, so something is wrong if you still have the problem. By opening a valve and allowing air and some brake fluid to leave, you can remove (or flush) air from your hydraulic braking system.

When the air gets into the hydraulic system due to normal wear and tear, it forms a mushy cushion between the spongy pedal and other components, rendering force transfer ineffective and giving the pedal a spongy feel.

Though bleeding is an essential part of keeping the system in check and should be done on a regular basis, if you are unfamiliar with its physics and don’t perform it frequently enough, you may cause problems.

2. Brake Fluid Pollution

After bleeding, spongy brakes are caused by more than just air flowing from the outside. The quantity of brake fluid is crucial, but so is the quality. Hydraulic brake fluid is hygroscopic, which means it draws moisture. At the brake rotors, a car’s kinetic energy is converted to thermal energy.

When you press the brake pedal, some of the kinetic energy is converted into heat for the braking rotors. When the fluid inside is old and contains more moisture, the heat continues to heat it, causing it to boil over time.

Boiling water molecules produce steam, which traps air inside the system. As a result, changing your fluid on a regular basis is recommended.

The fact that this symptom does not arise every time you drive or test the brake is the most evident evidence. This issue will be covered in colder weather or if you only go for a short distance because it must heat up first.

3. Brake Hose Problems

Another issue that causes air in brake lines after bleeding is a hydraulic system leak.

Because your hydraulic system operates under pressure, a leak is a distinct possibility. If the liquid can seep out, then air can also flow in. Although a fluid leak is usually obvious, a wet, greasy patch around the braking components or lines should be inspected. Air will enter the wires through even the tiniest leak.

Brake lines, brake nipples, caliper seals, and brake hoses are the most leak-prone brake components. However, you should check the entire system for any potential leaks.

Checking the wet portions of the system, where the fresh fluid seeps out, is an easy way to figure out where the leak is.

The rubber hose may or may not show signs of wear and tear or age. The hose has an inner and outer wall that prevents fluid loss if one of them ruptures.

The weaker wall, on the other hand, permits the hose to inflate and expand rather than transferring fluid pressure to the brake caliper, similar to squeezing a balloon in the middle. The hose swelling results in a nasty spongy mushy pedal.

How To Fix The Spongy Brakes?

brakes still spongy after bleeding

Although this is unusual, there is a workaround. We’ll give you some pointers on how to fix brakes that are still spongy after bleeding.

1. Release Brake Pressure Properly

The brake system is critical for cars to maintain speed and handle unforeseen traffic conditions. To make the car brake system perform more smoothly on every journey, you must exhaust the braking system.

Prepare the following instruments to exhaust the braking system: brake fluid, hydraulic hose, air release kit (wrench, plastic pipe), and cleaning cloth.

To begin, park the automobile on a flat surface with the parking brake applied. Locate the master cylinder and brake fluid reservoir under the hood. Empty the brake fluid reservoir of any old brake fluid. Then add some new brake fluid.

Raise the front of the vehicle with the hydraulic jack. Then support the front of the vehicle with two four-legged killing squads. Remove the hydraulic clutch and repeat with the back of the vehicle.

Locate the air outlet valve of the right rear brake assembly. The exhaust valve is usually attached to the cylinder body on the brake assembly. Attach a plastic hose to the drain valve, and the other end of the plastic hose to an external brake fluid reservoir.

Request assistance from a friend or family member by pressing the brake pedal several times and then holding it in the lowest position. Slowly open the drain valve after that. The plastic tube will carry old oil and air bubbles into the reservoir. 

Close the air exit screw after the brake fluid has stopped flowing, then release the pedal.

Remind the support person not to let off of the brake pedal while you’re exhausted. Rep until no more air bubbles appear and fresh brake fluid comes out of the drain valve.

Tighten the drain valve and remove the plastic hose from the valve once the venting is finished. Clean the surrounding region and any brake fluid that has gotten lodged on the exhaust valve.

Check the brake fluid reservoir’s oil level. It’s important to keep in mind that the oil level should not be too low. If there are indicators of a significant oil deficit, additional should be added before performing the air discharge procedure on the remaining three wheels. Because while exhausting the other wheels, low oil can allow air to enter the master cylinder.

For the next wheels, repeat the exhaust process as described above, one by one, until the last wheel is reached. Continue checking the brake fluid level and brake pedal height after that. Then lower the vehicle and test drive it.

2. Fix The Brake Fluid Pollution

Because old fluids are more susceptible to air and moisture, you should completely replace them with new juice. Also, don’t let any air in during the procedure.

If you bled incorrectly the first time, bleed again using a proper procedure.

Using a higher DOT fluid is another approach to avoid this happening soon. In comparison to prior versions, a DOT 5 has a higher boiling point and is less prone to steam and air problems.

3. Parts Replacement

Any broken part that is beyond repair should be replaced. Replace all brake lines, as the others are likely to fail soon, and then bleed the system. If there are only tiny leaks, you can cover them with specific tapes or sealants.

Frequent Asked Questions

Q: After bleeding my brakes, why do I have no brake pressure?

After bleeding your brakes, you may notice that you have no braking pressure: Brake lines with air. There’s a brake fluid leak somewhere in the system (check your fluid level to verify sure it’s still there) The master cylinder seal is faulty.

Q: When there is air in the system, how do I firm up my brake pedal?

The most typical cause of a soft brake pedal is that the system is still inflated. Pumping the brake pedal softly a few times is the easiest way to diagnose this problem. With each modest press of the pedal, the pedal should become firmer.

Q: Is it possible for air to get caught in the master cylinder?

Air can migrate to the high point if it enters the left front or right rear wheel circuits. If the vehicle’s brake pedal is low and/or spongy and the master cylinder is situated at an angle, trapped air could be the problem.

Final thoughts

Spongy brakes after bleeding are uncommon, but not unheard of. We’ve already explained why. Furthermore, we offer solutions to that situation. I hope you are able to solve it. Please leave your queries in the comments box so that we may assist you.

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