How Does a Hydraulic Clutch Work?

A hydraulic clutch works in a similar manner to hydraulic brakes, using a master and slave cylinder connected with a pipe to disengage the pressure plate. When the driver presses on the clutch petal, it forces pressure into the master cylinder; the pressure forces fluid through the pipe to the slave cylinder.

The hydraulic system replaces the system of levers and cables on a traditional manual clutch. In some applications, the manufacturer finds it easier to direct the hydraulic tube than the cables. This is especially true in rear-engine and mid-engine vehicles.

As in other hydraulic systems, users must keep the fluid level in the hydraulic clutch reservoir full. If the fluid level drops, it introduces air into the system. Remove air by bleeding the fluid at the slave cylinder. Drivers should check the fluid level as a part or their routine maintenance and add the manufacturer's recommended fluid to fill the reservoir.

The clutch is a system that transfers energy from the engine to the transmission of the vehicle in the engaged position. The driver must disengage the clutch to change gears in a manual transmission. A strong spring clamps the pressure plate into position. The manual or hydraulic system works against this spring to remove the pressure and stop the energy transfer.