About Hydraulic Clutches

A car clutch is the component that engages and disengages the rotation of the wheels. Without a clutch, your vehicle's wheels would either spin continuously or not at all. Cars with a manual clutch require drivers to engage the clutch through the use of the clutch pedal. What happens in between the driver's foot and the wheels depends on the type of clutch installed on the car. This article discusses the less popular version, hydraulic clutches.

Features

  • There are two main types of linkage designs for clutches. A mechanical clutch connects the clutch pedal to the rest of the system via a cable or shaft and lever. In contrast, a hydraulic clutch uses a master cylinder and actuator rod. Through the connection of high-pressure tubing, this system operates similarly to a hydraulic brake system.

Function

  • How exactly does a hydraulic clutch work? When the driver pushes the clutch pedal, a plunger is pressed into the cylinder. This results in fluid being forced out of the cylinder and into the slave cylinder. From here, the pressure of the fluid engages the push rod into the throw-out bearing. This series of actions disengages the clutch. Removing pressure from the clutch pedal reverses the effects.

Benefits

  • The most important benefit of a hydraulic clutch is the ease of use. A mechanical clutch requires much greater force to move the chain of events along. As such, the driver must press much harder on the clutch pedal each time she changes gears. A hydraulic clutch benefits from requiring only a tap of the foot.

Considerations

  • Due to the improved ease of operation, hydraulic clutches are typically found on vehicles with a rear-engine construction. This is because the distance between clutch pedal and throw-out bearing are much farther apart and therefore require greater force to operate. Front-engine vehicles are relatively easy to control with a mechanical clutch, so they typically do not include a hydraulic clutch.

Expert Insight

  • There are a few disadvantages to hydraulic clutches that limit their use. They are more expensive, more complex and heavier than mechanical clutches. Therefore, they find limited use in today's modern auto market.