The rotary type power steering gear is designed with all components in one housing.
The power cylinder is an integral part of the gear housing. A double-acting piston allows oil pressure to be applied to either side of the piston. The one-piece piston and power rack is meshed to the sector shaft.
The hydraulic control valve is composed of a sleeve and valve spool. The spool is held in the neutral position by the torsion bar and spool actuator. Twisting of the torsion bar moves the valve spool, allowing oil pressure to be directed to either side of the power piston, depending on the directional rotation of the steering wheel, to give power assist.
REMOVAL & INSTALLATION
Power Steering Pump
Remove the reservoir cover and use a suction gun to empty the reservoir. Disconnect the hoses from the pump and tie them in a raised position to prevent oil spillage. Loosen the pump adjusting screw and remove the pump belt, then take out the retaining bolts and remove the pump and reservoir.
On cars equipped with air conditioning, the pump is removed from underneath the vehicle.To install:
Position the pump assembly and install the retaining bolts. Be sure there is clearance between the pump bracket and the engine front support bracket. Install the hoses and place the pump belt on the pulley. Adjust the belt to 1 / 2 inch deflection, then tighten the adjusting screw.
Connect the hoses to the pump assembly.
Fill the reservoir to within 1 / 2 inch of the top with automatic transmission fluid type A.
Start the engine and rotate the steering wheel several times to the right and left to expel air from the system, then recheck the oil level and install the reservoir cover.
Bleeding the System
Fill the pump reservoir to within 1 / 2 in. of the top. Start and run the engine to attain normal operating temperatures. Now, turn the steering wheel through its entire travel three or four times to expel air from the system, then recheck the fluid level.
Checking Steering Effort
Run the engine to attain normal operating temperatures. With the wheels on a dry floor, hook a pull scale to the spoke of the steering wheel at the outer edge. The effort required to turn the steering wheel should be 3 1 / 2 -5 lbs. If the pull is not within these limits, check the hydraulic pressure.
To check the hydraulic pressure, disconnect the pressure hose from the gear. Now connect the pressure gauge between the pressure hose from the pump and the steering gear housing. Run the engine to attain normal operating temperatures, then turn the wheel to a full right and a full left turn to the wheel stops.
Hold the wheel in this position only long enough to obtain an accurate reading.
The pressure gauge reading should be within the limits specified. If the pressure reading is less than the minimum pressure needed for proper operation, close the valve at the gauge and see if the reading increases. If the pressure is still low, the pump is defective and needs repair. If the pressure reading is at or near the minimum reading, the pump is normal and needs only an adjustment of the power steering gear or power assist control valve.
Worm Bearing Preload and Sector Mesh Adjustments
Disconnect the pitman arm from the sector shaft, then back off on the sector shaft adjusting screw on the sector shaft cover.
Center the steering on the high point, then attach a pull scale to the spoke of the steering wheel at the outer edge. The pull required to keep the wheel moving for one complete turn should be 1 / 2 - 2 / 3 lbs.
If the pull is not within these limits, loosen the thrust bearing locknut and tighten or back off on the valve sleeve adjuster locknut to bring the preload within limits. Tighten the thrust bearing locknut and recheck the preload.
Slowly rotate the steering wheel several times, then center the steering on the high point. Now, turn the sector shaft adjusting screw until a steering wheel pull of 1-1 1 / 2 lbs. is required to move the worm through the center point. Tighten the sector shaft adjusting screw locknut and recheck the sector mesh adjustment.
Install the pitman arm and draw the arm into position with the nut.