What is the reason for air reappearing in the brake system a few days after bleeding?
2 Answers
Brake bleeding fails to completely remove air for the following reasons: When the master cylinder retracts but the wheel cylinder does not, a certain vacuum is created in the pipeline. If the rubber seal of the wheel cylinder is not tight, air will enter. Below is relevant information about brakes: 1. Introduction: Braking, also known as deceleration, refers to the action of stopping or reducing the speed of moving locomotives, vehicles, other transportation tools, or machinery. The general principle of braking is to fix a wheel or disc on the high-speed shaft of the machine and install corresponding brake shoes, bands, or discs on the machine base, which generate braking torque under external force. The brake device, also known as a decelerator, is a mechanical braking device that can slow down the speed. 2. Purpose: To reduce speed or stop the vehicle. The principle of braking is to convert the kinetic energy of the vehicle into heat energy and dissipate it. The kinetic energy comes from the power provided by the engine, which requires fuel combustion to perform work.
Last time I had my car repaired, I also encountered the issue where air reappeared in the brake system a few days after bleeding. This is usually due to a minor undetected leak in the system. Possible causes include loose clamps on the brake lines, aging or leaking seals in the wheel cylinders or master cylinder, or loose connections in the brake hoses. Air can seep into the system as the fluid moves, causing the brake pedal to feel spongy. I recommend observing the system for a few days after bleeding and checking all connections for signs of fluid leakage, especially in older vehicles where rubber components tend to harden and deform. Additionally, if the brake fluid absorbs too much moisture, prolonged use can generate vapor, creating false air pockets. It’s important to replace the fluid promptly and ensure the system is completely sealed. Overall maintenance should be thorough, and it’s best to have a pressure test performed to identify any leaks, preventing the risk of brake failure while driving.
