Most power steering systems work by using a belt driven pump to provide hydraulic pressure to the system. This hydraulic pressure is generated by a rotary-vane pump which is driven by the vehicle's engine. As the speed of the engine increases, the pressure in the hydraulic fluid also increases, hence a relief valve is incorporated into the system to allow excess pressure to be bled away.

While the power steering is not being used, i.e. driving in a straight line, twin hydraulic lines provide equal pressure to both sides of the steering wheel gear. When torque is applied to the steering wheel, the hydraulic lines provide unequal pressures and hence assist in turning the wheels in the intended direction.

Some more modern implementations of hydraulic systems also include an electronic pressure valve which can reduce the hydraulic pressure of the power steering lines as the vehicle's speed increases. (Variable assist power steering)

6 SIGNS YOU NEED TO REPLACE YOUR POWER STEERING PUMP

  • If your car squeals when you turn the ignition, it may be a sign that your steering pump needs to be replaced. It could also be a loose or worn accessory belt, so check that first. However, if the noise continues every time you turn the ignition, a faulty pump may be the cause.

  • Groaning noises emanating from your car every time you turn the wheel means you should take your car to a mechanic as soon as possible. Groaning means the steering system isn’t getting the fluid it needs to function. If left unchecked, this can lead to a need for costly repairs.

  • If you turn your steering wheel and the car doesn’t respond immediately, the problem may be the steering pump. This can lead to dangerous situations on the road, so be sure to get your car to a mechanic to get the steering inspected.

  • If it’s taking more strength than usual to turn your wheel, it means that the power steering fluid isn’t getting to the components designed to help you steer more easily. A faulty pump may be to blame.

  • While doing regular checks under the hood, if you notice your car’s power steering fluid is always low, it’s time to get your vehicle serviced. Low power steering fluid is a sign that there’s a leak somewhere in your steering system, and it may be your pump. Check the ground underneath your car’s parking spot. Power steering fluid is usually red or orange.

  • Grey power steering fluid indicates that the fluid has oxidized and won’t work as well as it should. Oxygen may be getting into the fluid through the pump. Metal flakes in the liquid are also a clue that something is amiss in your steering system.

Frequently asked questions

Can you drive without hydraulic power steering?

When driving without power steering fluid is prolonged, damage to the steering pump is inevitable. As a result, the pump vanes that produce heat are left with no lubrication, fuse down, and increase the risk of damaging the drive belt.

What is the work of hydraulic power steering?

Hydraulic power steering systems work by using a hydraulic system to multiply force applied to the steering wheel inputs to the vehicle's steered (usually front) road wheels. The hydraulic pressure typically comes from a gerotor or rotary vane pump driven by the vehicle's engine.