GM Service Manual Online
For 1990-2009 cars only

Power Steering Pump Flow Control Valve Replacement - Off Vehicle CB Series

Disassembly Procedure


    Object Number: 391490  Size: SH
  1. Remove the O-ring union fitting (5) from the hydraulic pump housing assembly (1).
  2. Remove the O-ring seal (4) from the O-ring union fitting (5).
  3. Remove the control valve assembly (3).
  4. Remove the flow control spring (2).

Assembly Procedure


    Object Number: 391490  Size: SH
  1. Install the flow control spring (2) to the hydraulic pump housing assembly (1).
  2. Install the control valve assembly (3).
  3. Lubricate the O-ring seal (4) with power steering fluid.
  4. Install the O-ring seal (4) onto the O-ring union fitting (5).
  5. Notice: Refer to Fastener Notice in the Preface section.

  6. Install the O-ring union fitting (5) into the hydraulic pump housing assembly (1).
  7. Tighten
    Tighten the fitting (5) to 75 N·m (55 lb ft).

Power Steering Pump Flow Control Valve Replacement - Off Vehicle Return Tube

Disassembly Procedure


    Object Number: 391544  Size: SH

    Important: Handle the pump with care. Do not carry the hydraulic pump housing assembly (1) by the return tube (2).

    Important: Replace the hydraulic pump housing assembly (1) if the return tube (2) is cracked or loose. Do not attempt to repair the hydraulic pump housing assembly (1).

  1. Inspect the return tube (2) on hydraulic pump housing assembly (1).

  2. Object Number: 391535  Size: SH
  3. Remove the O-ring union fitting (5) from the hydraulic pump housing assembly (1).
  4. Remove the O-ring seal (4) from the O-ring union fitting (5).
  5. Remove the control valve assembly (3).
  6. Remove the flow control spring (2).

Assembly Procedure


    Object Number: 391535  Size: SH
  1. Install the flow control spring (2) to the hydraulic pump housing assembly (1).
  2. Install the control valve assembly (3).
  3. Lubricate the O-ring seal (4) with power steering fluid.
  4. Install the O-ring seal (4) on to the O-ring union fitting (5).
  5. Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  6. Install the O-ring union fitting (5) into the hydraulic pump housing assembly (1).
  7. Tighten
    Tighten the O-ring union fitting (5) to 75 N·m (55 lb ft).