When you get in your car and head out for the day, you have a lot on your mind. You might be thinking about the meeting you’re attending, or what errands you need to run on your way home.
What we don’t think about is the trouble we might face a few miles down the road. We assume our cars will work, and will protect us in the event of something going wrong.
How about your braking system? Think it’s working okay on your vehicle? A study put out by the National Highway Traffic Safety Administration showed that 22 percent of accidents were caused by brake-related issues. That means they didn’t function correctly, and were the major cause of why the accident occurred.
The braking system is one of the major systems of your vehicle. And at the heart of the braking system is the master cylinder, in charge of sending brake fluid down through the brake lines to the brake caliper. This allows the caliper to control the brake pads, squeezing against the rotors to slow your vehicle down, keeping it in control and safe as you move throughout your day.
Like every part of your braking system, the master cylinder will only last for so long. And when it does, it causes disruption in the system and puts your vehicle at risk.
Luckily, there are warning signs to watch for before your master cylinder goes bad.
What is a master cylinder?
Before we get into some of the potential problems with your master cylinder, let’s get a clearer understanding of its importance to the brake system.
The brake system moves into action as you step on the brake pedal. Through hydraulics, the force of the brake pedal moves pressurized brake fluid through the line, down into the caliper. The caliper then squeezes the brake pads at each wheel into the brake rotor, which in turn causes friction at the base. This action is what slows down the wheel rotation, bringing it eventually to a stop.
None of this would be possible without the master cylinder providing the brake fluid into the braking system. If something is wrong with the master cylinder, it shows up in the form of a braking system that doesn’t work as intended.
The brake pedal is connected to a pushrod. By applying pressure to the brake pedal, it pushes the pushrod deeper into the master cylinder. Inside are two pistons and spring, which move into action as the pushrod connects.
Inside is a reservoir of brake fluid, which floods the master cylinder during this process. The reservoir stays shut when in motion, but as the pushrod releases the ports to the reservoir, it causes the fluid to rush in.
This fluid follows the brake line until it eventually sets the calipers into motion. As you release the brake pedal, the springs pop back into place, and the braking system returns to its original position, waiting for your next movement.
Signs of problems with the master cylinder
Just by understanding how the braking system works should allow you to see where potential problems can begin. This also helps you keep a watchful eye on ways to prevent problems before they start.
Brake pedal feels spongy
This is one of the easiest symptoms to notice. As you drive your car, notice how things feel when everything is running well. Then do a quick assessment every time you slip behind the wheel. Do you see differences from the last time you drove? Stepping on the pedal should always be a responsive move. If it feels squishy, almost like stepping on a sponge, it could be a problem with the master cylinder. The brake pedal may also sink closer to the floor, and not pop back into its regular position. This happens because of a problem with the seal inside. If they are worn or damaged, they can allow fluid to leak. That means there won’t be enough pressure to squeeze the pads into place.
Brake fluid is low
While you don’t need to replace your brake fluid regularly like you do motor oil, it can eventually be low enough it needs a refill. Different cars have different requirements. The easiest way to tell how often your brake fluid needs replacing is to check with your car’s manufacturer, or read your owner’s manual. Then stick with a schedule, and be sure to replace it in a timely manner. Without brake fluid, you could have total brake failure. That’s dangerous at best.
Brake warning light
Luckily, today’s vehicles are designed to give you advanced warning of potential problems. If you have a newer car, chances are it’s designed with pressure sensors that will alert you if brake fluid levels drop too low. Some cars have a “brake light” indicator, while others may illuminate a “check engine” light that can mean many different things. Don’t ignore warning lights. Stopping by and allowing us to check for potential problems can alert you to small problems that are easily fixed, avoiding bigger, more expensive problems down the road.
While the master cylinder is designed to be an enclosed system, as it wears down, seals can be damaged and allow contaminates inside. This usually coincides with a brake pedal that loses responsiveness, but you can also pay attention to the brake fluid color. Brake fluid is clear, possibly with a slight yellow tint. If it darkens to brown or black, then there may be a problem with the brake fluid. You might also notice gunk forming along the master cylinder casing.
What does it mean to replace a master cylinder?
The cost of replacing your master cylinder depends on the make and model of your vehicle.
If you catch the problem early enough, it may be a simple process of flushing your braking system and inputting fresh, clean brake fluid back into the system.
If the master cylinder has sustained damage or is worn from age, it might be time to replace it altogether. This is something one of our mechanics can help you with, and make suggestions for the best way to repair your car and keep it safe.
Don’t ignore your master cylinder. At the first sign of trouble, stop by and have your brake system evaluated. It’s better to stop potential problems quickly and avoid bigger problems down the road.