What is wrong with the steering rack

Many drivers have heard of the steering wheel angle sensor or steering wheel position sensor. However, few people realize the full significance of this control element. Do you know that the operation of the entire electric power steering depends on the condition of the sensor?

Steering rack failures

Leakage

Hydraulic power steering units are equipped with high-pressure seals that keep the oil inside the steering rack and protect it from leaks. Rubber and Teflon seals are also used in hydraulic power steering systems to ensure proper oil circulation. Sealing elements are made of durable and wear-resistant materials such as oil-resistant rubber, Teflon, and metal alloys.

Unfortunately, there are no materials invented yet that are eternal, so all parts wear out over time and lose their properties. One of the most common faults in steering racks is oil leakage.
Steering wheel angle sensor - electric power steering component that determines the position of the steering wheel within a range of 720 degrees in each direction. The sensor is most often installed on the electric column under the steering wheel, less frequently on the pinion.

One of the most common faults in steering racks is oil leakage.

Why does hydraulic power steering leak:

• Oil seals of the distributor and hydraulic actuator are worn due to normal mechanical wear. Moving parts of the steering rack (rack body, rack bar, pinion) rub against oil seals, gradually wearing them out.
• Parts of the steering rack corrode when shields are worn out and moisture penetrates the device. Rust on the piston and pinion accelerates the wear of oil seals and causes rapid leakage.
• O-rings and seals lose their shape and physical properties over time due to constant pressure, oil, and high temperatures, causing the steering rack to leak.
• As a result of the breakdown of the bearing in the distributor or wear of the bushings.

If there are oil stains under the car, the hydraulic oil tank level constantly drops, and the wheels respond to steering with a delay, check the condition of the steering rack. These symptoms may also indicate leaks in the power steering pump, hoses, and tank. Therefore, exercise caution during inspection and do not forget to check other components of the steering system.
A decrease in the level in the hydraulic oil tank is an obvious reason to check the steering rack.

In the case of steering rack leaks, air enters the system, causing additional load on the pump. If there is a lack of oil, and the system is clogged, the power steering pump will make noise, the steering system will become heavy, and the driving comfort will deteriorate.

To prevent leaks from the steering rack, it is sufficient to regularly check the condition of the shields, inspect the device for corrosion, replace sealing elements in a timely manner, and regularly service it.

Knocking and play

Drivers often complain about knocking around the front axle. Knocking is often accompanied by play in the steering wheel, which is particularly noticeable when driving on bumpy roads. In most cases, the faulty steering rack is to blame. Knocks and play can occur in any steering rack, regardless of its design and type.

Improper adjustment of the steering rack

Improperly adjusted steering racks usually knock, as do units with a worn side mount for the gear rack. In such cases, the rack and worm shaft of the distributor collide with each other, and the teeth of the shafts are damaged.

If the position of the gear rack is misadjusted, in addition to the knocking noise, the driver will feel characteristic vibrations in the steering wheel. If the vehicle is equipped with a mechanical steering rack, there will be no other signs of incorrect adjustment.

In power steering racks, a loose rack bar causes improper operation of other system elements.

In hydraulic steering racks, a faulty distributor mechanism wears out oil seals and causes leaks.

In the case of an electric unit, knocking and loose parts of the unit gradually damage the components of the electric drive system, affecting the position and operation of sensors. This malfunction will have a significant impact on the vehicle's steering; for example, the steering wheel may become stiff, turn spontaneously, sway, or not return to the center position.

In this case, it is worth entrusting the inspection and adjustment of the steering rack to a service center to eliminate vibrations and knocking. Careful and cautious driving will help avoid knocking and play in the device.

Worn lateral thrust

Worn lateral thrust is another cause of knocking and play, consisting of several elements. What fails in the lateral thrust:

• The foil insert is worn out. It is a plastic insert mounted on the thrust piston. The foil insert protects the rack bar from excessive friction against the metal thrust piston. A worn insert will cause the thrust piston to shake and wear out quickly.
• The spring in the lateral thrust is cracked or corroded. The spring will gradually wear out and lose its physical properties. The more aggressively you drive, the faster the spring will wear out.
• Corroded and jammed lock nut prevents adjustment of the position of the rack bar.

If there is a problem with the spring, replace the worn part or the entire unit. Prevention in this case is simple: drive carefully, take care of the vehicle, and perform timely inspections.

Worn pinion bearings

Another reason for knocking and play is worn pinion bearings. Bearings are not eternal either – they "age," deteriorate due to mechanical friction, rust on the pinion, and careless driving on uneven roads. To eliminate the problem, the worn bearing needs to be replaced, and the condition of the remaining pinion components should be checked for damage and corrosion.

Some drivers forget or are unaware of the existence of a dust seal that covers the pinion from above and protects it from rust and contaminants. It is worth periodically checking its condition – this protective element performs the same function as the steering rack cover.

Wear of the support bushings

The rack bar also knocks if the bushings are worn. More precisely, it is not the bushing but the steering rack elements that are out of place. A steering rack with worn bushings will knock but will not have vibrations and play in the steering wheel. The causes of bushing wear are standard: mechanical wear, corrosion on the shaft, sudden shocks, and vibrations during driving.

Attention! Knocking at the front axle may also be caused by faulty tie rods and tie rod ends. Shock absorber struts can also knock in these cases. However, in these cases, you will not feel any vibrations in the steering wheel. If there is knocking but the steering rack is in order, check the chassis – it may be causing the problem.

Cracking during turning

Unpleasant creaking sound in the front axle area when turning the steering wheel is a clear sign of corroded steering rack elements. The following parts may creak:

• Pinion bearings;
• Torsion and pinion mounting point on the steering column;
• Worm shaft and rack bar

Now you know what causes pinion bearing wear.

Rust and wear on the teeth of the worm and rack bar

Rust on the teeth of the worm and rack is a common problem with steering racks whose owners do not care about the condition of the dust seal. In a situation where it breaks, moisture enters the device, causing corrosion.

First of all, corrosion spreads to the central shafts of the mechanisms. The reason is simple – most of the time, the car is driven in a straight line, so the lubricating oil does not reach the pinion. When turning, the pinion rubs against theracks, causing rust.

When the steering rack is clogged, the pinion and worm shaft grind the rust, making a characteristic creaking sound. If you hear it, carefully disassemble the steering rack and clean the parts from rust.

Rust on the teeth accelerates wear of the pinion bearings. In the worst case, the teeth may wear out unevenly, which will cause knocking during driving.

Irregular wear of the teeth

Irregular wear of the teeth is another problem caused by rust. In this case, it is not enough to clean the rack bar and pinion from rust – you need to adjust the axial gap of the pinion and rack bar.

This procedure requires removing the pinion and rack bar  and adjusting the gap between them using special tools. Unfortunately, not every driver can cope with such a task on their own, so if there are irregularities in the operation of the steering rack, it is better to contact a service center for help.

Vibrations during driving

If the steering wheel vibrates while driving, the distributor bearings are most likely worn out. Bearings are the weakest link in the power steering, as they wear out quickly and lose their properties. When the bearings wear out, the distributor and the entire steering system begin to vibrate.

It is almost impossible to determine the worn bearing by external signs – no oil stains or broken parts are visible. The only way to detect a problem is to disassemble the gearbox and check the condition of the bearing. If the bearing is cracked or jammed, replace it with a new one, and the vibrations will disappear.

Clogging of the rack bar

In some cases, the distributor bearings remain intact, but the steering wheel begins to vibrate. This happens if the rack bar of the worm is clogged with dirt and rust.

The rack bar requires constant lubrication, and the oil is supplied through small holes. When driving on dirty roads, the pinion is clogged, the rack bar does not receive enough oil, and the steering rack start to vibrate.

If the pinion is clogged, do not disassemble the steering rack – remove the pinion, clean it, and reinstall it in place. This will be enough to eliminate the vibrations and restore the normal operation of the power steering.

Problems with Steering Wheel Operation

A heavy steering wheel usually indicates damage to the power steering pump or power steering actuator. Difficulty in turning the steering wheel also occurs in case of power steering gear leakage, improper operation of the distributor mechanism, excessive side pressure, and circumferential wear in the distributor housing.

Circumferential Wear

The steering gear distributor mechanism redistributes fluid in the hydraulic actuator chambers and makes driving comfortable and easy. Malfunctions in the distributor primarily affect the ease of driving the car.

Circumferential wear is a common problem that every driver encounters over time. The Teflon rings of the distributor valve rotate with it, press hard against the housing wall, and eventually erode. Gradually, grooves appear on the inner wall, the rings stop self-tightening and effectively stopping oil flow. Pressure drops and the steering wheel becomes heavier. Also, when trying to turn the steering wheel in an unheated car, the steering wheel will stick and move intermittently.

To fix the malfunction, the distributor housing was sleeve-lined. For this purpose, a hole is drilled in the inner wall to press in a sleeve with a diameter appropriate for the steering gear distributor mechanism. The sleeves are made of bronze.

It's not without reason that we indicated that every driver experiences this malfunction. There are no methods to protect the unit from circumferential wear, but this process can be slowed down.

During operation, metal shavings accumulate in the fluid, which damage the power steering components. To ensure longer exploitation of the distributor housing, one should maintain oil quality, change it at appropriate times, and not forget about system flushing. And best of all, periodically remove, disassemble, and flush the rail - then there will be a guarantee of removing metal shavings.

Distributor Coil and Torsion Wear

Distributor malfunctions don't result only from circumferential wear. For example, if the coil mounts are worn and oil holes are blocked, the coil will move up and down on the shaft and block the oil holes.

O-rings are mounted on the coil, which are required for proper oil circulation. If the seals deteriorate, pressure will drop and the steering wheel will become stiff.

Like any other element, the torsion will wear and abrade over time. If the torsion is worn or operating improperly, the steering wheel will wobble, the wheels will react too slowly or won't react at all.

To fix distributor malfunctions, worn parts must be replaced. The simplest way to extend distributor life is careful and considerate driving, avoiding bumpy roads, and contacting service at the first signs of trouble.

Electric Power Steering Malfunctions

If there's a malfunction in the electric power steering gear, besides a tight steering wheel, a characteristic EPS error message will appear on the dashboard. Electric power steering can fail for many reasons.

In short, most power steering malfunctions are caused by moisture, which causes short circuits and contact oxidation. The power steering and actuator fail due to sudden impacts, frequent driving on uneven roads, and aggressive driving. These causes also lead to improper sensor operation. Poor service is another reason for unexpected failures of electric power steering or EPS-H pump actuator.

Wear of the Housing's Internal Surface

Partial loss of power usually occurs when the rack piston hits the gear housing and creates a groove in it. The effects of the failure are aggravated by old oil containing lots of metal shavings. As a result, the piston doesn't seal tightly against the housing and cylinder chamber sealing is disrupted. The driver will then have difficulty turning the steering wheel from the center position, but after the piston passes the groove, the steering system will become noticeably lighter.

A damaged housing must be replaced. After such a failure, there is no other way to restore the gearbox to its original condition. Potholes on the internal surface of the gear housing result from frequent driving on uneven roads, aggressive driving, collisions with obstacles, and sharp impacts.

Rack Piston Wear

Steering force is also partially lost in case of wear to the piston seals or the piston itself. Seal and piston rod wear is caused by constant friction, sudden shocks, and vibrations while driving on bumpy roads. In all cases, the result is the same - pressure in the cylinder chambers is improperly distributed and the steering system becomes heavy. Symptoms are especially noticeable at low engine speeds when the power steering pump doesn't generate high pressure.

To fix the malfunction, the seals must be replaced. If the malfunction involves the piston, it will also need to be replaced. As in most cases, to avoid malfunctions, it's enough to be careful and attentive on the road, not use the car in off-road conditions unless absolutely necessary. Also, it's not worth forgetting about scheduled maintenance.

Now you know what breaks in steering gears, what signs signal each type of malfunction, and how to repair and prevent failures. We hope this information is useful and will help you stay on wheels in all conditions.

Summary

The power steering is an important component of the vehicle, ensuring the driver's comfort and safety. The main elements of the power steering are the hydraulic pump, steering rack, and hydraulic actuator. The steering rack is responsible for converting the rotary motion of the steering wheel into the linear motion of therack bar.

There are several types of steering racks, including mechanical, hydraulic, and electric. Each type has its advantages and disadvantages. Mechanical steering racks are simple and reliable but have a heavy steering wheel. Hydraulic steering racks provide a more comfortable and smoother ride but require regular maintenance. Electricsteering racks are modern and efficient but are more expensive and complex.

Common steering rack problems include oil leakage, knocking, play in the steering wheel, creaking during turning, uneven wear of teeth, vibrations during driving, and corrosion of rack elements. These problems can be caused by various factors, including wear and tear, lack of maintenance, and driving conditions.

Diagnostics of the steering rack involves checking the steering wheel for play, testing the steering rack with the engine off, checking the steering rack with the engine running, and inspecting the hydraulic system. Once the cause of the steering rack malfunction is identified, appropriate measures can be taken to repair or replace the faulty components.

Regular maintenance, careful driving, and timely repairs are essential to ensure the proper functioning of the steering rack and, consequently, the overall safety and performance of the vehicle. If you experience any problems with your steering rack, it is recommended to consult with a qualified mechanic or visit a service center for a thorough inspection and necessary repairs.