The cause of a complete failure of the hydraulic booster is most often a broken pump drive belt. Regularly check the condition of the belt - it may be worn or loose. One of the signs of a weak belt tension is the appearance of kickback (pushback) on the steering wheel. This is usually most noticeable when starting the car from a place when the wheels are turned to the full.
Maintain the correct amount of fluid in the booster reservoir. If necessary, add fluid only to the brand specified in the service manual. Please note that automatic transmission fluid can not be used for all power steering. There are many different brands of liquids on the market. The wrong fluid can ruin all the seals in the system.
Since the liquid is used not only as a working fluid of the hydraulic system, but also as a lubricant, it is very important that its level does not fall below normal, otherwise the pump may fail. Also keep the fluid clean. Dirty or expired fluid will quickly destroy the pump and rack and pinion hydraulic seals, requiring costly repairs later. Fluid changes are rarely required. If you want to drain the fluid, you must open the cap of the expansion tank, disconnect one of the pipelines of the system and turn the steering wheel from side to side several times to squeeze the fluid out of the hydraulic system. There is usually no special hole for draining the liquid. Filling with new fluid is done through the expansion tank. As a rule, in this case, air plugs are formed in the hydraulic system that disrupt its performance. They should be removed. The easiest way to do this is as follows. Start the engine, open the expansion tank cap and bleed the system by turning the steering wheel several times from one extreme position to another. As the hydraulic system is pumped, the fluid level in the reservoir will decrease. Repeat this procedure until it stabilizes. After that, add liquid to the required level and close the lid, after checking if the vent is not clogged in it (if it exists).
The most common malfunction of hydraulic boosters is fluid leakage. With such a defect, cars usually fail to pass inspection. Some older hydraulic systems allowed some leakage of fluid through bearings, shafts, etc., as it is almost impossible to make them completely tight. Regularly inspect the system components from all sides for the timely detection of possible leaks from pipelines and fittings, as well as from loose pipelines and other parts.
Find out if the tubes and hoses are rubbing against the chassis and suspension parts. A hydraulic line failure can cause fluid to break through the covers. When checking, turn the steering wheel from one extreme position to another. Small leaks can often be repaired by introducing commercially available sealing additives into the fluid. However, this will only be a short-term measure. If the pump fails, it can be repaired using a new seal repair kit. Replacing the seals won't do much if the pump is badly worn.
For those who like to do everything themselves, repairing the pump will not present much difficulty. However, before installing the repaired pump on the car, it is advisable to check it on the stand. If you suspect that the pump is worn out, contact a power steering specialist to check its operating pressure and correctly identify the problem. Generally speaking, the numerous advantages of power steering far outweigh the problems posed by its possible malfunctions. It is worth, after you have traveled in a car with a modern system, to change to a car that does not have a power steering system, and you will immediately "feel the difference".