Q: How Does a Hydraulic Clutch System Work?

A hydraulic clutch system works using various hydraulic components to actuate the clutch when the pedal is pushed in. The system works similar to how the brakes work on your vehicle. The clutch hydraulics consists of the clutch pedal, connecting push rod, clutch master cylinder, hydraulic metal or plastic piping, and the clutch slave cylinder.

The clutch pedal is a solid lever hooked to a pivot point above the driver’s feet area. The pedal lever connects to a rod using a clevis pin. The rod connects directly to the clutch master cylinder. When the pedal is pushed in, it will push the rod out toward the master cylinder. The rod will push in the master cylinder, causing it to push out hydraulic fluid into the fluid line connected directly to it. When the fluid leaves the master cylinder into the piping, it will flow into the clutch slave cylinder. The fluid will cause the slave cylinder to push in the clutch pedal or the clutch pressure plate depending on design.

The only adjustment on these hydraulic systems is at the clutch pedal to keep the free travel correct. The system from the master cylinder to the slave cylinder is a closed system that must not have any air in it. The fluids should be replaced on a regular basis just like your brake fluid is changed.

The hydraulic clutch will feel easier to push in when compared to other clutch systems like lever or cable types. The system uses the same fluid as most brake systems. Note that some systems only use silicone-type fluids and using the wrong fluid can damage the seals and cause leaks.