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SECTION 6C

POWER STEERING GEAR

Caution : Disconnect the negative battery cable before removing or installing any electrical unit or when a tool or equipment could easily come in contact with exposed electrical terminals. Disconnecting this cable will help prevent personal injury and damage to the vehicle. The ignition must also be in LOCK unless otherwise noted.

SPECIFICATIONS

General Specifications

Application
Standard
Capacity
0.69 Liter
Lubricant
Power Steering Fluid DEXRON® -II D
Type
Rack & Pinion
Rack Gain
45.78 mm/rev
Rack Stroke
136 ± 1.0 mm
Steering Angle
Inner
39.5°
Outer
33°
Rack
Straight (Bending Limit)
0.1 mm

Fastener Tightening Specifications

Application
N•m
Lb-Ft
Lb-In
Coupling Flange Pinch Bolt
22
16
-
Outer Tie Rod Hex Nut
50
37
-
Outer Tie Rod Lock Nut
45
33
-
Power Steering Line Fittings-Cylinder End
27
20
-
Power Steering Line Fittings-Valve End
18
13
-
Steering Gear Inlet and Outlet Pipe Fittings
28
21
-
Steering Gear Retaining Bracket Nuts
60
44
-

SPECIAL TOOLS

Special Tools Table


KM507B
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KM-507-B
Ball Joint Remover

KMJ26610
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KM-J-26610
Installer

COMPONENT LOCATOR

Rack And PinionSteering Gear


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  1. Power Steering Gear
  2. Outer Tie Rod
  3. Cylinder Line
  4. Dust Boot
  5. Steering Gear Clamp
  6. Intermediate Shaft

DIAGNOSIS

Power Rack and Pinion Steering Gear

Hissing Noise

Checks
Action
Check the steering coupling joints for looseness.
Tighten the steering coupling joints.
Check the power steering hose for contact with other components.
Be sure the power steering hose is correctly fitted into the hose clips.

Rattling Noise in Steering Gear

Checks
Action
Check the power steering hose for contact with the body.
Be sure the power steering hose is correctly fitted into the hose clips.
Check the steering gear for insufficient lubrication.
Lubricate the steering gear.
Check the steering gear mounting for looseness.
Tighten the steering gear mounting bracket nuts.
Check the outer tie rods for improper installation.
Tighten the outer tie rod joints. Replace the outer tie rods as needed.

Poor Return of Steering Wheel to Center

Checks
Action
Check the steering wheel for contact with the turn signal housing.
Adjust the turn signal housing.
Check the steering coupling for binding or looseness.
Replace the steering coupling flange.
Check the power steering pump flow control valve for sticking and improper alignment.
Replace the power steering pump.
Check the wheel alignment.
Adjust the wheel alignment.
Check the wheel bearings for wear or damage.
Replace the wheel bearings.
Check the steering gear-to-column joints for improper installation.
Adjust the steering coupling flange on the steering gear and the steering column. Replace the coupling flange as needed.
Check the outer tie rods and the ball joints for binding or looseness.
Tighten the tie rods and the ball joints. Replace the tie rods and the ball joints as needed.
Check the steering gear adjustments.
Perform a straight-ahead check.
Check the steering column shaft seal for rubbing on the shaft.
Replace the shaft seal.
Check the steering shaft bearings for binding.
Replace the steering shaft bearings.

Momentary Increase in Effort When Turning the Wheel Quickly

Checks
Action
Check the power steering pump for internal leaks.
Replace the power steering pump.
Check the hoses for damage or restricted flow.
Replace the power steering hoses and pipes.
Check the power steering fluid level.
Fill the power steering fluid reservoir.
Check the power steering pump flow control valve for sticking and improper operation.
Replace the power steering pump.

Steering Surges or Jerks When Turning with Engine Running

Checks
Action
Check the power steering pump for insufficient pressure.
Replace the power steering pump.
Check the power steering pump flow control valve for sticking and improper operation.
Replace the power steering pump.
Check the pump drive belt for slippage.
Tighten the pump drive belt.
Check for air contamination in the power steering system.
Bleed the power steering system.

Steering Vibrates During Low Speed or Static Steering

Checks
Action
Check for air contamination in the power steering system.
Bleed the power steering system.
Check the pump drive belt for looseness.
Tighten the pump drive belt.

Excessive Wheel Kickback or Loose Steering

Checks
Action
Check for air contamination in the power steering system.
Bleed the power steering system.
Check the wheel bearings for wear or damage.
Replace the wheel bearings.
Check the steering gear mounting for looseness.
Tighten the steering gear mounting bracket nuts.
Check the steering gear-to-column joints for improper installation.
Adjust the steering coupling flange on the steering gear and the steering column. Replace the coupling flange as needed.
Check the outer tie rods and ball joints for looseness.
Tighten the tie rods and the ball joints. Replace the tie rods and the ball joints as needed.

Hard Steering or Lack of Assist (Especially During Parking)

Checks
Action
Check the steering gear-to column joints for improper installation.
Adjust the steering coupling flange on the steering gear and the steering column. Replace the coupling flange as needed.
Check the power steering pump flow control valve for sticking and improper installation.
Replace the power steering pump.
Check the power steering pump for insufficient pressure.
Replace the power steering pump.
Check the power steering pump for internal leaks.
Replace the power steering pump.
Check for a loose or a worn steering coupling.
Tighten the steering coupling flange. Replace the steering coupling flange as needed.
Check the pump drive belt tension.
Adjust the pump drive belt tension.

Power Rack and Pinion Steering Gear Bench Testing

Removal, Setup and Testing Procedure

Notice : Pressure checks or pressure and flow checks may also be conducted using this setup.

  1. Disconnect and remove the power steering gear. Refer to "Rack and Pinion Assembly" in this section.
  2. Place the power steering gear on a bench next to the vehicle.
  3. Disconnect the pressure line at the point where the hose connects to the pipe. Extend this line in order to reach the power steering gear on the bench.
  4. Disconnect the return line from the the power steering fluid reservoir. Extend this line in order to reach the power steering gear on the bench.
  5. Connect the power steering pipes to the power steering gear.
  6. Start the engine and allow it to idle for 10 seconds.
  7. Check the power steering fluid level. Refer to Section 6A, Power Steering System.
  8. Start the engine and turn the rack and pinion stub shaft to a full turn in each direction. Hold the shaft against each stop for 5 seconds.
  9. Inspect for possible leak points. Refer to Section 6A, Power Steering System.

Installation Procedure

  1. Stop the engine.
  2. Disconnect the power steering pipes from the power steering gear.
  3. Remove the extensions and reconnect the pressure and return lines.
  4. Install and connect the power steering gear. Refer to "Rack and Pinion Assembly" in this section.
  5. Start the engine and allow it to idle for 10 seconds.
  6. Check the power steering fluid level. Refer to Section 6A, Power Steering System.

MAINTENANCE AND REPAIR

ON-VEHICLE SERVICE


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Rack and Pinion Assembly

Tools Required

KM-507-B Ball Joint Remover

Removal Procedure

  1. Position the tires straight ahead by turning the steering wheel.
  2. Remove the Interm Shaft. Refer to Section 6E, Steering Wheel And Column.

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  3. Remove the Front Tires.
  4. Disconnect the Steering Gear Inlet and Outlet pipe fittings.
  5. Drain the Power Steering fluid from the Rack And Pinion.

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  6. Remove the outer tie rod hex nuts. Refer to "Outer Tie Rod" in this section.

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  7. Remove the ball joint hex nuts and disconnect the stabilizer shaft from the knuckle by removing the stabilizer shaft link assembly. Refer to Section 2C, Front Suspension.

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  8. Remove the cross member by removing the nuts and bolts to the underbody.

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  9. Remove the Rack and Pinion assembly by disconnecting the steering gear retaining bracket nuts.

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Installation Procedure

  1. Install the Rack and Pinion assembly by connecting the steering gear retaining bracket nuts.

    2. Tighten
    Tighten the steering gear retaining bracket nuts to 60 N•m (44 lb-ft).


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  2. Install the cross member by tightening the nuts and bolts to the underbody.

    3. Tighten
    Tighten the cross member by tightening the nuts and bolts to the underbody to 170 N•m (125 lb-ft).


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  3. Install the ball joint hex nuts and connect the stabilizer shaft to the knuckle by tightening the the bolt with stabilizer shaft link assembly. Refer to Section 2C, Front Suspension.

    4. Tighten
    Tighten the ball joint hex nuts to knuckle to 55 N•m (41 lb-ft). Tighten the bolts of stabilizer shaft to the knuckle to 50 N•m (37 lb-ft).


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  4. Install the outer tie rod hex nuts.

    5. Tighten
    Tighten the outer tie rod hex nuts to 50 N•m (37 lb-ft).


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  5. Connect the Steering Gear Inlet and Outlet pipe fittings.

    6. Tighten
    Tighten the nuts of Steering Gear Inlet and Outlet pipe fittings to 28 N•m (21 lb-ft).

  6. Install the Front Tires. Refer to Section 2E, Tires and Wheels.
  7. Refill the Power Steering fluid.

    8. Notice : When adding fluid or making a complete fluid change, always use DEXRON II D power steering fluid. Failure to use the proper fluid will cause hose and seal damage and fluid leaks.


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  8. Install the Interm Shaft. Refer to Section 6E, Steering Wheel And Column.
  9. Install the steering wheel and column.

    10. Important : After all the operations with the steering gear, be sure to check the exact straight-ahead position of the steering in each case. Refer to "Straight-ahead check" in this section.


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Outer Tie Rod

Tools Required

KM-507-B Ball Joint Remover

Removal Procedure

  1. Remove the wheel. Refer to Section 2E, Tires and Wheels.
  2. Remove the outer tie rod hex nut and disconnect the outer tie rod from the steering knuckle using the special tool KM-507-B.

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  3. Loose the tie rod lock nuts and remove the outer tie rod.

    4. Important : Before loose the tie rod lock nut, mark the position of the lock nut for easy alignment after installation procedure.


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Installation Procedure

  1. Reposition the lock nut to the marks on the inner tie rod.
  2. Install the outer tie rod by twistion it onto the inner tie rod.
  3. Connect the outer tie rod to the steering knuckle.
  4. Perform a front toe adjustment. Refer to Section 2B, Wheel Alignment.
  5. Tighten the lock nut.

    6. Tighten
    Tighten the tie rod lock nut to 45 N•m (33 lb-ft).


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  6. Install the outer tie rod hex nut.

    7. Tighten
    Tighten the outer tie rod hex nut 50 N•m (37 lb-ft).

  7. Install the wheel. Refer to Section 2E, Tires and Wheels.

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Dust Boot

Tools Required

KM-J-22610 Installer

Removal Procedure

  1. Raise and suitably support the vehicle.
  2. Remove the wheel. Refer to Section 2E, Tires and Wheels.
  3. Remove the outer tie rod. Refer to "Outer Tie Rod" in this section.
  4. Remove the dust boot retaining clamps.

    5. Notice : In case of the driver side, remove the steering gear. Refer to "Rack and Pinion Assembly" in this section.

  5. Remove the dust boot.

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Installation Procedure

  1. Install the dust boot.
  2. Install the tie rod end dust boot retaining clamp. Install the cylinder end dust boot retaining clamp with the installer KM-J-22610.
  3. Install the outer tie rod. Refer to "Outer Tie Rod" in this section.
  4. Install the wheel. Refer to Section 2E, Tires and Wheels.
  5. Lower the vehicle.

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Power Steering Gear Yoke Adjustment

Tools Required

GE-49210 Yoke Adjusting Tool

Adjustment Procedure

    Important : If rattle noise exists in the power steering gear perform the yoke adjustment for the power steering gear.

  1. Raise and suitably support the vehicle.
  2. Center the steering wheel.

  3. Remove the power steering gear. Refer to “Rack and Pinion Assembly” in this section.
  4. Loosen the locknut.

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  5. Install the yoke adjusting tool GE-49210 and hex socket wrench on the yoke plug and tighten the yoke plug clockwise until a torque of 5 N•m (44 lb–in) is obtained, then loosen it counterclockwise by 45 degrees.

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  6. Tighten the locknut on the yoke plug while holding the yoke plug stationary.

    7. Tighten
    Tighten the yoke plug locknut to 30 N•m (22 lb-ft).

  7. Install the power steering gear. Refer to “Rack and Pinion Assembly” in this section.
  8. Be sure to check the return ability of the steering wheel to center position after adjustment.

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Straight-Ahead Check

After all the necessary operations on the steering gear are completed, check the exact straight-ahead position of the steering in each case.
With the vehicle on the floor, place the steering wheel in the straight-ahead position. Mark the centerline of both tires on the floor. Turn the steering wheel all the way to the right and mark the new centerline of both tires on the floor.

Straight-Ahead Check Table

Step Action Value(s) Yes No
1
Place the steering wheel in the straight-ahead position.
Is the wheel in the correct position?
-
Go to Step 2
-
2
Is the steering coupling flange pinch bolt lying horizontally?
-
Go to Step 3
Go to Step 4
3
Is the steering wheel off center by more than 5 degrees?
-
Go to Step 5
Go to Step 6
4
The pinion is displaced on the rack. The steering pinion position must be corrected.
Is the repair complete?
-
Go to Step 2
-
5
Remove steering wheel and center on the spindle splines.
Is the repair complete?
-
Go to Step 3
-
6
Turn the steering wheel all the way to the right. Measure the inner and the outer angles of the tire centerline compared to the straight-ahead centerline. Do the angles match the value specified?
Inner angle: 39° 5'± 1° 30'
Outer angle: 34° ± 1° 30'
System OK
Go to Step 7
7
The rack assembly was not assembled correctly.
Repair, as needed.
Is the repair complete?
-
Go to Step 6
-

GENERAL DESCRIPTION AND SYSTEM OPERATION

Power Rack and Pinion

General Description

The power rack and pinion steering system has a rotary control valve which directs the hydraulic fluid coming from the hydraulic pump to one side or the other side of the rack piston. The integral rack piston is attached to the rack. The rack piston converts hydraulic pressure to a linear force which moves the rack left or right. The force is then transmitted through the inner and the outer tie rods to the steering knuckles, which turn the wheels.
If hydraulic assist is not available, manual control is maintained. However, under these conditions, more steering effort is required. The movement of the steering wheel is transferred to the pinion. The movement of the pinion is then transferred through the pinion teeth, which mesh with the teeth on the rack, causing the rack to move.
A vane-type pump provides hydraulic pressure for the system.
The boot and rack guide, the rack bearings, and the valve and pinion assembly are no longer serviceable on this vehicle. They must be replaced as whole units.


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