How To Tell If Your Clutch Master Cylinder Is Bad

The clutch master cylinder can be found on vehicles designed with manual transmission. It is directly connected to the clutch pedal and serves as the part of the hydraulic system responsible for generating hydraulic pressure. They are designed into two major categories based on their internal functions responsible for generating hydraulic pressure. These two categories include center-feed type systems and seal over port systems.

Signs Of A Bad Clutch Master Cylinder

Soft Pedal

When you notice with your foot that the pedal has lost resistance, it is called a “soft pedal”. This problem can be caused by two things, a leak in the master cylinder or the slave cylinder. This leak can come about when there is a problem with the seals.

Hard To Shift Gears

Sometimes when the master cylinder is failing, shifting gears is difficult. Without proper depression of the clutch, changing gears becomes difficult.

Pedal Gets Stuck To The Floor

When the hydraulic to the clutch stops working, the clutch pedal will remain on the floor. This might be because the master cylinder is damaged and needs replacing. The car can’t be driven in this condition until a replacement is made.

Low Fluid

When you notice that the clutch fluid is always low and needs refilling more often than normal, you probably might notice a leak in the master cylinder. A crack or hole somewhere in the clutch system can also be responsible. To counter the problem effectively, all parts of the clutch hydraulics should be checked properly.

Fluid Rise In The Reservoir

You can do the following test with the help of an assistant if you have a bad master cylinder. Ask your assistant to press down on the clutch while you look to find out if the clutch fluid in the reservoir elevates when the clutch is pressed down and rises when it is released. If the result is affirmative, your master cylinder is bad and needs replacing.   

Noisy Engagement

You might hear a loud noise when you hold down the clutch pedal at a light with the brake on while the car is in gear. This noise might be because the master cylinder is leaking and won’t conserve the release fork when the pedal is down.

Final Note

It is often advised to replace the master cylinder at the same time with the clutch slave cylinder. A failure in one of them encourages failure in the other. Some clutch master cylinders can be enhanced to cut costs. The clutch pedal needs to be adjusted after every replacement of the clutch master cylinder. Always reintroduce the seals whenever you dismantle the master cylinder or slave cylinder. More information can be gotten from your vehicle’s factory manual.


Helm, H. (2019, 10 16). 7 Signs of a Bad Clutch Master Cylinder. Retrieved from Doityourself:

Stevens, M. (2019, 12 20). 4 Symptoms of a Bad Clutch Master Cylinder (and Replacement). Retrieved from

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