Feel Confident Behind the Wheel: Maintain Your Own Car

Braking Problems? Why the Master Cylinder May Be to Blame

20 July 2018

Craig Hicks

Your car's braking system has many individual components, but in essence it works by pushing hydraulic pressure against a set of friction pads, to force the road wheels to decelerate. This entire process only works if the hydraulic system is operating at maximum efficiency and in large part, this is controlled by the brake master cylinder. This should really be one of the first places to look if you encounter any issues with your braking system, but what should you be looking for?

How the Cylinder Works

The master cylinder is usually made from bronze or aluminium and sits underneath the fluid reservoir. It is connected via a piping system to each wheel and via a metal rod to the pedal inside the passenger cabin. Within the cylinder is a large valve that forces brake fluid down the lines towards each wheel whenever you depress the brake pedal. As hydraulic fluid cannot be compressed it will cause an equal reaction at the other end, forcing the brake pads against each disc, which in turn slows the wheel.

Perishing Rubber

Within the cylinder are some rubber seals that help to keep the fluid in its place and prevent dirt from entering. They will deteriorate over time, though, and tiny flecks of rubber can find their way into the fluid itself. When this happens, the solution will turn a darker colour and will lose some of its consistency and when it does so, it will not be able to provide the same amount of pressure as before. You'll be able to feel that something is wrong through the ball of your foot as you press the brake pedal. It will feel "mushy," or it may even sink all the way to the floor.

Air Leaks

Air may have entered the system as well, if any of the rubber hoses have become compromised. Unfortunately, brake fluid can also absorb minute particles of water and this will affect the vehicle's overall efficiency and your ability to stop.

Dashboard Warning

On modern cars, you may also notice a "check engine light" on the dashboard. Often, a pressure sensor is installed within the master cylinder and when something starts to go wrong, it will trigger an alert to prompt you to check the fluid pressure.

Remember the Cylinder

Most people focus on the brake pads when they service their vehicle, but in truth the master cylinder is equally, if not more important. Make sure that you have a good look at it when you next visit your mechanic if you need further brake repairs.

Share  

Search