A car’s braking system consists of several components. One of them is a brake master cylinder, also known as the master cylinder. It converts the pressure from the brake pedal into hydraulic force, which then applies to the brakes. Doing so allows the vehicle to slow down or stop.

Let’s go through the role of a master cylinder in a car, how it works, its types and components. 

The brake master cylinder is an essential component in different types of car braking systems. It converts the force exerted by the driver’s foot on the brake pedal into hydraulic pressure. When the brake pedal is depressed, it activates a piston within the master cylinder, pressuring the brake fluid. 

This pressurised fluid transmits through the brake lines to the brake callipers or wheel cylinders at each wheel. It forces the brake pads or shoes against the brake rotors, resulting in friction that slows down or stops the vehicle. 

In addition, the brake cylinder master uses a piston with different-sized surfaces to multiply hydraulic force. With minimal pedal pressure, it generates high pressure in the brake lines, ensuring effective braking.

The brake master cylinder consists of several key components. They include:

The reservoir stores the brake fluid, which is among the essential car fluids for the operation of the braking system. It consists of a plastic or metal container with a cap for easy access for topping up brake fluid.

The piston is housed within the cylinder bore of the cylinder. When the brake pedal is pressed, the piston moves forward, pressurising the brake fluid in the cylinder bore.

This is the cylindrical chamber where the piston moves back and forth. It is sealed to prevent brake fluid leaks and maintain hydraulic pressure.

Some master cylinders feature dual chambers to separate the front and rear brake circuits for safety reasons. The primary chamber is responsible for one set of brakes (usually the front), while the secondary chamber controls the other set (mostly the rear).

Seals prevent leaks and maintain hydraulic pressure within the master cylinder. They are usually made of rubber to withstand the pressures generated during braking.

These ports allow car brake fluid to enter and exit the cylinder master. There are usually two ports per chamber—one for fluid inlet and one for fluid outlet.

In some modern cars, a fluid level sensor in the master cylinder reservoir alerts the driver when the brake fluid level is low.

Here are the two main types of brake master cylinders. 

This type has a single piston and cylinder bore. It is used in older and some smaller vehicles such as kei cars. Moreover, in a single master-cylinder setup, all brake circuits (front and rear brakes) are controlled by a single-cylinder bore.

A dual master cylinder features two piston and cylinder bore assemblies, each responsible for controlling a different brake circuit. One cylinder bore controls the front car brakes, while the other controls the rear brakes. 

Besides, this setup provides redundancy and safety because if one brake circuit fails, the other can still provide partial braking. It allows the driver to maintain some control over the vehicle. Moreover, dual master cylinders are standard in most modern cars and considered safer than single master counterparts.

A failing or damaged brake master cylinder can lead to various car braking problems. Here are the common symptoms:

One of the most noticeable signs of a failing master cylinder is a soft or spongy brake pedal. If the pedal feels mushy or requires more effort to depress than usual, it could indicate an internal leakage within the master cylinder.

Visible brake fluid leaks around or beneath the vehicle or near the brake lines indicate a failing master cylinder. Leaks can occur due to worn seals or cylinder bore damage, leading to hydraulic pressure loss and reduced braking effectiveness.

A lit brake warning system light signals various brake system issues including a failing master cylinder. If the brake fluid level drops below a certain threshold due to a leak or leakage within the cylinder brake master, the warning light may illuminate.

Contaminated brake fluid, which appears dark or murky instead of clear, can indicate internal corrosion or seal degradation within the brake cylinder. Besides, it affects the brake performance and should be addressed promptly.

A failing master cylinder may cause inconsistent braking performance, such as brakes that grab or pull to one side during braking. It results from the unequal distribution of hydraulic pressure to the brake callipers or wheel cylinders, leading to uneven braking force.

The brake master cylinder converts the force from the brake pedal into hydraulic pressure. It then activates the brakes to slow down or stop the car.

Master cylinder failure can be caused by internal seal wear or corrosion, leading to brake fluid leaks and loss of hydraulic pressure.

Driving with a bad brake master cylinder poses significant safety hazards. It should be avoided until the issue is resolved by a professional mechanic.

That is all on the brake master cylinder and its role in a car’s braking system. However, in case of any malfunctions, it poses serious hazards to car safety and must be looked into immediately. 

If your car is also breaking down frequently due to damaged components, it’s time to switch to a better ride. For that, sift through these used cars for sale in the UAE that offer several listings under different budgets.

To learn more about different types of car components and their working, keep reading dubizzle’s auto blog.