around fittings. in hoses. at the gearbox seals, or at the rack-and-pinion assembly.
To check for leaks. wipe the fluid-soaked area(s) with a clean rag. Then have another person start and idle the engine. While watching for leaks, have the steering wheel turned to the right and left. This action will pressurize all components of the system that might be leaking. After locating the leaking component. remove and repair or replace it.
POWER STEERING PRESSURE TEST. - A power steering pressure test checks the operation of the power steering pump, the pressure relief valve, the control valve. the hoses. and the power piston. Basic procedures for performing a power steering pressure test are as follows:
Using a steering system pressure tester, connect the pressure gauge and shutoff valve to the power steering pump outlet and hose. Torque the hose fitting properly.
With the system full of fluid, start and idle the engine (with the shutoff valve open) while turning the steering wheel back and forth. This will bring the fluid up to temperature.
Close the shutoff valve to check system pressure. Note and compare the pressure reading with manufacturer's specifications.
CAUTION
Do NOT close the shutoff valve for more than 5 seconds. If the shutoff value is closed longer, damage will occur to the power steering pump from overheating.
To check the action of the power piston. control valve. and hoses, measure the system pressure while turning the steering wheel right and left (stop to stop) with the shutoff valve open. Note and compare the readings to the manufacturer's specifications. If the system is not within specifications, use the manufacturer's service manual to determine the source of the problem.
BLEEDING A POWER STEERING SYSTEM. - Any time you replace or repair a hydraulic component (pump. hoses, and power piston), you should bleed the system. Bleeding the system assures that all of the air is out of the hoses, the pump, and the gearbox. Air can cause the power steering system to make a BUZZING sound. The sound will occur as the steering wheel is turned right or left.
To bleed out any air, start the engine and turn the steering wheel fully from side to side. Keep checking the fluid and add as needed. This will force the air into the reservoir and out of the system.
The most common problems of a steering system are as follows:
Steering wheel play
Hard steering
Abnormal noises when turning the steering wheel
These problems normally point to component wear, lack of lubrication. or an incorrect adjustment. You must inspect and test the steering system to locate the source of the trouble.
The most common of all problems in a steering system is excessive steering wheel play. Steering wheel play is normally caused by worn ball sockets, worn idler arm, or too much clearance in the steering gearbox. Typically, you shou Id not be able to turn the steering wheel more than 1 1/2 inches without causing the front wheels to move. If the steering wheel rotates excessively, a serious steering problem exists.
An effective way to check for play in the steering linkage or rack-and-pinion mechanism is by the dry-park test. With the full weight of the vehicle on the front wheels, have someone move the steering wheel from side to side while you examine the steering system for looseness. Start your inspection at the steering column shaft and work your way to the tie-rod ends. Ensure that the movement of one component causes an equal amount of movement of the adjoining component.
Watch for ball studs that wiggle in their sockets. With a rack-and-pinion steering system, squeeze the rubber boots and feel the inner tie rod to detect wear. If the tie rod moves sideways in relation to the rack, the socket is worn and should be replaced.
Another way of inspecting the steering system involves moving the steering components and front wheel BY HAND. With the steering wheel locked, raise the vehicle and place it on jack stands. Then force the front wheels right and left while checking for component looseness.
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