The power steering pump determines how easily the steering wheel turns, how quiet the system is and how long it will last. Pressure stability, noise level, power transmission efficiency and even fuel consumption depend on the design of the pump. If the pump is not selected correctly or its maintenance is started, the steering wheel becomes heavy, howling or vibrations appear.
What are the types of power steering pumps
Power steering hydraulic system It works on the principle of creating and maintaining pressure in a liquid circuit. The pump pumps the fluid to the distributor, which directs it to the hydraulic cylinder, and then to the return circuit. The main function of the pump is to ensure a stable flow of fluid regardless of engine speed.
In power steering, the pump is responsible for creating and maintaining pressure, which helps the driver turn the steering wheel with minimal effort. The hydraulic system consists of a reservoir with working fluid, a pump, a distributor, a hydraulic cylinder and a return circuit. When the engine is running, the pump begins to pump fluid through the belt drive. It enters the distributor, which supplies pressure in the right direction depending on the turn of the steering wheel, and then returns to the reservoir.
Gear Pump Power Steering
The principle of operation is simple: two metal gears in the housing create pressure. It is inexpensive, resistant to dirt, but it works noisily and vibrates. It is used mainly in old car models and commercial vehicles.
Advantages:
- Simple and reliable design;
- Resistance to dirt and temperature extremes;
- Unpretentiousness to liquid.
Disadvantages:
- noisy operation, especially at idle;
- Tangible vibrations;
- Lower efficiency compared to paddle models.
Service:
Regular fluid replacement (every 40-50 thousand km), checking the seals and the condition of the gears. If the pump begins to leak or "whistle", the seals are probably worn out or the casing is damaged.
Power steering vane pump
Uses a rotor with retractable blades. Its advantage is smooth, quiet operation even at low rpm. Such pumps are installed in most middle-class passenger cars. They require clean fluid and timely replacement of the filter.
Advantages:
- Quiet and smooth operation;
- Stable pressure even with changing engine speeds.
Disadvantages:
- High sensitivity to liquid quality;
- Gradual wear of the blades and hull surfaces.
Service:
Use only the recommended hydraulic fluid, keep it clean. Contamination or overheating quickly leads to blade seizing. It is useful to periodically flush the system and change the filter.
Rotary Pump Power Steering
The most modern type. Uses an eccentrically positioned rotor that creates high pressure and stable flow. It is compact and efficient, but expensive to produce and difficult to repair, so it is found mainly in premium cars.
Advantages:
- High Performance and Pressure;
- Minimal noise;
- compactness.
Disadvantages:
- complexity of repair;
- High cost of manufacturing and spare parts.
Service:
Fluid change at least once every 50 thousand km, bearing and temperature control. For durability, only recommended oils are used, since the wrong viscosity destroys rotor pairs.
What and why breaks down in power steering pumps
In gear pumps, gear teeth are most often worn and seals are worn out. This is manifested by howling and a drop in pressure. In paddle valves, blades stick due to dirt or old fluid, in rotary blades - rotor seizures or bearing destruction.
Pump wear is affected by:
- low fluid level or overheating;
- Contamination in the system;
- Long-term operation at high speeds without cooling;
- Incorrect oil viscosity.
How to fix:
- when the pressure decreases, check the level and condition of the liquid;
- replace filter, seals, gaskets;
- In case of hum, check the pulley and bearings.
Repair is advisable if the body does not have cracks; In case of significant wear, it is better to replace the pump.
How to protect the power steering pump from breakdown
The durability of the power steering pump directly depends on the cleanliness of the fluid, the temperature and proper care of the system. Even small particles of dirt or overheating can cause wear on the blades, gears or rotor. To avoid costly repairs, there are a few key rules to follow:
- Check your fluid level and condition regularly. A drop in the level leads to air capture, noise and a decrease in pressure. If the liquid has darkened or has a burning smell, it needs to be replaced urgently.
- Do not mix different types of hydraulic fluids. The mixture may foam or form a sediment that clogs the channels and damages the pump. When switching to another type of liquid, the system is completely flushed.
- Monitor the tension of the drive belt. A loose belt causes slippage, noise and pressure reduction, while an over-tight belt overloads the bearings.
- Do not hold the steering wheel in the extreme position for more than 5 seconds. At this point, the pressure in the system is maximum, the fluid does not circulate, the pump overheats, which leads to seizure of surfaces.
- Carry out maintenance of the system every 50-60 thousand km. Filter should be changed, the tank and hoses should be flushed, and the pressure in the system should be checked with a pressure gauge.
- Avoid water and dust. Moisture causes corrosion of internal parts, and dust settles on the pump shaft and quickly wears out the seals.
Compliance with these simple measures allows you to extend the life of the power steering pump by two to three times. Regular system health checks, clean fluid and proper operation ensure that the steering wheel operates quietly even after years of use.