How To Tell If ATV Master Cylinder Is Bad? – Discuss Some Factors In Detailed

The Brake Master cylinder is the heart of the braking system of modern ATV vehicles.

Some factors indicate that your ATV vehicle has a bad master cylinder. These include abnormal brake pedal behavior, contaminated brake fluid, leaking brake fluid, and engine lights turning on.

The master brake cylinder plays an important role in the overall function of the vehicle; without it, the vehicle cannot function properly.

Therefore, it is necessary to check for any damages and failures in the master cylinder to avoid unwanted accidents.

In this article, we will discuss these factors in detail so that you can understand them easily and the importance of checking your master brake cylinder.

Discuss Some Factors In Detail

Abnormal Brake Pedal Working:

One of the symptoms of the bad master cylinder is abnormal brake pedal behavior.

Abnormal Brake Pedal Working:
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When the brake pedal is pressed, the pressure is converted to hydraulic pressure, which stops the vehicle.

In case when the master cylinder is not working well, it badly affects the normal behavior of the brake pedal.

In this condition, the pedal is harder to press or will sink into the vehicle floor and not move up like normal pedals.

The brake pedal may feel spongy. This condition results when the air gets in the brake lines and prevents the brake fluid from flowing properly through them, which is a sign of a bad master cylinder.

Contaminated Brake Fluid:

Brake fluid is the alcohol-based fluid that is used in braking systems. It works by absorbing the pressure from the brake pedal, converting it into hydraulic pressure, and sending it to the front and back wheels, causing the vehicle to stop.

When the brake fluid contamination, its color changes, badly affecting its functions and is a sign of a bad master cylinder.

The brake fluid contaminates when it comes in contact with the air (resulting from the broken rubber seals of the filler cap), and the oxygen in the air reacts with the fluid and oxidizes it.

Therefore, keeping your filler caps tightly sealed and checking for broken rubber seals is always recommended to avoid any air contact.

The contaminated brake fluid causes many problems, such as the brakes may become locked and no braking occur due to the contaminated fluid.

Check for the fluid. If its color is changed, then replace it immediately with the fresh one (with having clear yellow color) for the smooth working of the system. 

Leaking Brake Fluid:

The brake fluid leakage is caused by the damage to the components of the brake system,rusting and normal wear and tear in the bleeder valves..

Leaking Brake Fluid:
Source: rac

For a master cylinder to function properly to stop the vehicle, it requires an adequate amount of brake fluid.

If there is a leak in the master cylinder, there will be a lower level of brake fluid than required, making it very difficult or even impossible for you to stop the ATV vehicle.

Therefore, it is essential to take it seriously if you see a leakage and fix the issue. Otherwise, the brakes will not be able to stop the car, and it can result in a serious accident.

Check Engine Light Turns On:

The engine lights always help a lot in determining if something goes wrong with the master cylinder.

Mostly the brake fluid level and pressure sensors are present in modern ATV vehicles for determining any issue.

These sensors quickly determine if there is a problem with the brake fluid pressure.

If the pressure drops more than normal, it will indicate the problem through the engine light by turning on the warning lights.

Importance Of Checking Brake Master Cylinder: 

The brake master cylinder is the heart of the whole braking system of the ATV vehicle. It helps in controlling the ATV vehicle.

Importance Of Checking Brake Master Cylinder: 
Source: repairsmith

Moreover, the leakage of brake fluid (both external and internal leakage ) can result in serious accidents.

That’s why ,it is important to test your ATV vehicle braking Master cylinder to check for any problem.

Additionally, a bad master cylinder is unable to stop the vehicle when required, and  it is very dangerous to use a vehicle with a failed braking system.

If your engine lights are indicating a problem in the braking system or you observe any problem in it, you must get your vehicle’s master cylinder by a professional technician.

Never compromise on the master cylinder’s health as it is associated with your safe drive.

Replace it immediately when required, and never drive a car with a bad master cylinder.s


The health of the brake master cylinder is very important for the smooth working of your ATV vehicle.

Therefore, it is important to check for any problems in the master cylinder at times to avoid any serious accidents.

We have discussed the symptoms of a bad master cylinder for you, such as abnormal brake pedal behavior, contaminated brake fluid, leaking brake fluid, and engine light indication.

It is important to identify them. If you are facing any problem, switch your ATV vehicle braking system and fix it to enjoy your ATV ride without any fear.

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