How a Hydraulic Pump Works in a Vehicle

A hydraulic pump is used by several major components in your vehicle to perform very important functions. In most cars, hydraulic pumps are used to help stop your car, help you steer the vehicle and also used to help support the weight of your vehicle and provide a smoother ride.

Hydraulic Pumps in Brake Systems

Perhaps the most important hydraulic pump in your vehicle is the one that is located inside the master brake cylinder of your car. The master brake cylinder is the component that is responsible for pushing brake fluid throughout the brake lines to your car's brake calipers.

The hydraulic pump in the master cylinder provides the needed force or pressure to allow the brake calipers to engage the brake disc or brake pads with enough pressure to stop your vehicle. Brake systems in modern vehicles require a tremendous amount of hydraulic pressure in order to stop your car—especially at high speeds. Therefore, the hydraulic pump in your car's master cylinder is an integral part of the overall brake system. The brake fluid used to fill the brake fluid reservoir in your vehicle is a type of hydraulic fluid.

Power Steering Pumps

If you've ever driven an older vehicle that does not have power steering, then you know how hard the vehicle can be to turn at lower speeds. However, modern vehicles almost always come equipped with power steering that allows you to easily turn your vehicle, and even turn the steering wheel when the vehicle is at a complete stop.

The power steering pump in your vehicle is also a hydraulic fluid pump. In fact, power steering fluid is nothing more than hydraulic fluid. Whenever you turn your steering wheel, the hydraulic pump in your car's steering system pushes power steering fluid to the steering gear via a rotary vane hydraulic pump. In the majority of vehicles, the motor in the pump is powered by a belt and pulley.

As the belt powers the motor vanes and rotor in the power steering system, hydraulic fluid creates high-pressure that is used to help you turn your vehicle. The pressure created is applied to the steering bar which is attached to the steering wheel and pinion or worm gear (which turns the wheels). The more force or torque that you apply to the steering wheel, the more that the steering bar moves and turns the wheels.

Hydraulic Suspensions

Hydraulic suspensions are a popular modification for many vehicles these days. A hydraulic suspension is a form of suspension that uses independent dampers for each wheel of the vehicle and is controlled by a main control unit, which is normally placed inside the vehicle.

The independent dampers in a hydraulic suspension all utilize small hydraulic pumps to pressurize and depressurize the dampers at each wheel location. Individual dampers can be turned on and off with the flick of a switch inside the vehicle. The hydraulic pumps in the dampers create a high a level of forced pressure that allows the damper to be quickly pressurized and raise a particular part of the vehicle.