How Power Steering Works: Basics of Hydraulic Power Steering

Power steering is a critical component in modern vehicles that greatly assists drivers in controlling and maneuvering their cars. One common type of power steering system is hydraulic power steering, which uses fluid pressure to amplify the driver’s input and make steering easier. It’s the gold standard across a significant number of manufacturing and machinery industries worldwide, including the automotive industry.

What Is Power Steering?

Power steering is a vehicle system that helps drivers steer more easily by assisting in turning the steering wheel. Depending on the type of power steering system used, this assistance can be mechanical, hydraulic, or electric. Power steering systems help reduce the effort required to turn the wheel, especially at low speeds or when parking, making it easier and more comfortable for drivers to control their vehicles.

Power Steering Parts

The main components of a hydraulic power steering system include:

• Power Steering Pump: The engine drives the pump via a belt or pulley, creating hydraulic pressure in the system.
• Fluid Reservoir: Stores power steering fluid to maintain proper lubrication and cooling within the system.
• Pressure Hoses: Carry pressurised fluid from the pump to the steering gear/rack-and-pinion assembly.
• Steering Gear/Rack-and-Pinion Assembly: Converts hydraulic pressure into mechanical force to steer the vehicle.
• Valves and Seals: Controls fluid flow within the system and helps maintain proper operation.

 These parts work together in a closed-loop hydraulic circuit to assist in turning wheels when driver input is applied to the steering wheel.

The History of Power Steering

Power steering technology has evolved significantly over the years to improve driving comfort and control. The concept of power-assisted steering dates back to the early 20th century. First installed in 1876, hydraulic power steering revolutionised the agricultural, industrial, and manufacturing industries.  In the automotive industry, the first commercially available power steering system was developed by Chrysler Corporation in 1951 for the Chrysler Imperial model.

Over time, technological advancements led to the development of different types of power steering systems. Today, modern vehicles are equipped with sophisticated electronic and hybrid hydraulic power steering systems that offer improved efficiency, responsiveness, and customisation options compared to traditional systems. These innovations continue to enhance driver comfort and safety on the road.

How Power Steering Works

The basic principle behind power steering systems, specifically hydraulic power steering, is to assist the driver in turning the wheels by using hydraulic pressure generated by a pump. The vehicle’s engine powers the power steering pump, continuously circulating hydraulic fluid under pressure. When the driver turns the steering wheel, it transmits this input through a steering column shaft to either a rotary valve (in recirculating ball systems) or a rack-and-pinion gear set (in rack-and-pinion systems).

As the driver turns the wheel, it opens valves within the system that allow pressurised hydraulic fluid from the pump to enter either side of a piston or chamber connected to the steering linkage. The pressurised fluid exerts force on one side of the piston or chamber while returning fluid flows back into an interconnected reservoir.

This provides additional assistance in turning and moving parts within your car’s suspension system and directs the tyres to go in the desired direction. Adjusting the flow of pressurised fluid is based on speed and driving conditions, though various components such as control valves and cylinders help you turn with less physical effort.

Power Steering Maintenance

Proper maintenance of your vehicle’s power steering system is crucial to ensure its optimal performance and longevity. Here are some key maintenance tips:

• Check the Power Steering Fluid: Regularly check the level and condition of the power steering fluid. Low fluid levels or dirty, contaminated fluid can lead to poor system performance and potential damage.
• Change the Power Steering Fluid: It is recommended that the power steering fluid be changed according to the manufacturer’s guidelines or every 30,000 to 60,000 miles as part of regular maintenance.
• Inspect Hoses and Connections: Periodically inspect power steering hoses for signs of leaks, cracks, or wear. Ensure all connections are secure and free from any damage.
• Maintain Proper Belt Tension: If your vehicle has a belt-driven power steering pump, ensure the drive belt is correctly tensioned and in good condition.
• Address Unusual Noises or Vibrations: Any unusual noises, vibrations, or difficulty turning could indicate a problem within the power steering system.
• Regularly Flush the Hydraulic System: Flushing out old fluid at regular intervals helps prevent the build-up of debris and contaminants that can cause damage to components like pumps and seals.

Signs It’s Time to Replace Your Power Steering Pump

Several signs may indicate it’s time to replace your power steering pump:

• Noise: A whining noise when turning the steering wheel, especially at low speeds, can indicate a failing power steering pump.
• Difficulty Steering: If you notice increased resistance or difficulty in turning the steering wheel, it could be due to a loss of hydraulic pressure caused by a faulty pump.
• Fluid Leaks: Puddles or drips of power steering fluid under the vehicle may indicate a leak in the pump or one of its associated components.
• Contaminated Fluid: If the power steering fluid appears dirty, gritty, or has metal particles in it, this could be a sign that internal components within the pump are wearing out.
• Erratic Performance: Inconsistency in the power steering system, with sudden changes in ease of turning could signal problems with the pump.

Parts Breakdown for Hydraulic Power Steering

Every electric power steering system and hydraulic steering system is unique, but many vehicles and equipment with this technology feature the same core parts. These parts include:

• Vane pumps for a steady flow of oil
• Gear pumps that displace or move fluid
• Hydraulic piston pumps (for heavy-duty vehicles)

Some vehicles may have a wide assortment of other items, including electric motors, custom-built parts, external gear pumps, drive shafts, casings, and more. All play an important role in helping the electric power steering (EPS) or hydraulic power steering system work efficiently and quickly. The higher the system’s quality, the more nimble and reactive it will be.

Find Power Steering Parts and Components at White House Products, Ltd.

At White House Products, Ltd., we’re proud to serve a long list of clients with high-quality power steering parts and components, as well as a wide range of hydraulic products. We even offer customisation options to fit your specific needs. Browse our online shop or contact us directly for further assistance finding the power steering and hydraulic parts and components you need.