Glossary “hydraulic principles” Definition:
Use of a liquid under pressure to transfer force or motion, or to increase an applied force.

Glossary “hydraulic valve lifter” Definition:
Device using oil pressure to adjust its length and maintain zero valve clearance so that the valve noise is at a minimum. Also referred to as hydro.

Glossary “hydraulic press” Definition:
Piece of shop equipment that develops high forces using a hydraulic cylinder that is mounted to the fixture. Used to press parts on and off.

Glossary “hydraulic pressure” Definition:
Pressure exerted through the medium of a liquid.

Glossary “hydraulic fluid reservoir” Definition:
A part of a master cylinder assembly (both brake and clutch, if equipped) that hold reserve hydraulic fluid.

Glossary “hydraulic lever” Definition:
Means to multiply force using additional stages of mechanical leverage.

Glossary “hydraulic lifter” Definition:
Valve lifter located between the camshaft and pushrod that uses internal oil pressure to cause the lifter to expand lengthwise.

Glossary “hydraulic lifter leak down” Definition:
Hydraulic leakage between between the lifter plunger and body. It allows for heat expansion in the valvetrain parts and helps reduce lifter pump-up during valve float.

Glossary “hydraulic modulator” Definition:
Part of an antilock brake system that controls the application of hydraulic pressure to each wheel during a antilock brake condition.

Glossary “hydraulic brakes” Definition:
Braking system using hydraulic pressure to press the brake shoes against the brake drums.

Glossary “hydraulic clutch” Definition:
Clutch that is actuated by hydraulic pressure.