Is The Master Cylinder To Blame For Your Braking Problems? Here Is How To Find Out

The master cylinder plays the important role of converting the force applied onto the pedal into hydraulic pressure. Any problems with your master cylinder are therefore likely to have devastating effects on the effectiveness of your vehicle's braking system. This makes knowing how to detect signs of master cylinder defects important. Here are tips that will come in handy in helping you do so.

Soft brake pedal movement

When pressing against the brake pedal, you should experience a little bit of resistance. This is because pressing the pedal simply forces the master cylinder's piston to push the liquid through the brake lines. Naturally, this action should generate an opposing force. However, if there isn't enough fluid in the cylinder or if there are leaks or air in the braking system, the resistance generated won't be as much as expected and thus causing a soft brake pedal. This makes a soft brake pedal one of the easiest of detecting master cylinder failure.

Low brake fluid level

When there is a crack or a hole in the master cylinder, the brake fluid in the cylinder will leak. A leak can also occur when your vehicle has defective master cylinder O-rings. All these things will have the effect of lowering the overall brake fluid levels of your vehicle. By running a clean rag along the lines next to the cylinder or on the master cylinder itself you will be able to confirm whether a master cylinder leak is what is messing with your vehicle's braking efficiency.

Contaminated brake fluid

When contaminated, brake fluid usually changes into a black or dark brown color. Check the brake fluid reservoir and if it contains dark brown or black brake fluid, then you likely have a defective master cylinder.

For the master cylinder to effectively translate the brake pressure into hydraulic pressure, it has to be air-tight. To this end, manufacturers usually fit the master cylinder with rubber seals. These seals usually wear out over time. And when they do, they usually expose the brake fluid to the environment, something that then leads to contamination – in addition to a soft brake pedal since weak seals usually make pressure loss possible.

Illuminated Check Engine Light

Some modern vehicles have pressure and fluid level sensors located in the master cylinder. Any abnormal pressure and level readings are bound to cause the illumination of the Check Engine Light. And given the central role that the master cylinder plays when it comes to not only creating hydraulic pressure, but also holding brake fluid, this is a reliable sign of master cylinder defects. Contact a semi truck repair shop for more help.