GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2003 🢒 Astro - 4WD 🢒 Engine 🢒 Engine Mechanical - 4.3L 🢒 Cylinder Head Replacement - Right Side

Removal Procedure
  1. Disconnect the battery negative cable. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical.
  2. Remove the engine cover. Refer to Engine Cover Replacement in Interior Trim.
  3. Remove the engine cooling fan. Refer to Fan Replacement in Engine Cooling.
  4. Remove the intake manifold. Refer to Lower Intake Manifold Replacement .

    5. Object Number: 317450 Size: SH
  5. Remove the spark plug wire harness support.
  6. Remove the exhaust manifold. Refer to Exhaust Manifold Replacement - Right Side in Engine Exhaust.

    7. Object Number: 475837 Size: SH
  7. Remove the generator mounting bracket. Refer to Generator Replacement in Engine Electrical.
  8. Remove the generator mounting bracket stud from the cylinder head.
  9. Remove the engine wiring harness bolt from the rear of the right cylinder head.
  10. Remove the valve push rods. Refer to Valve Rocker Arm and Push Rod Replacement .
  11. Remove the cylinder head and the gasket. Refer to Cylinder Head Removal - Right Side .
  12. Clean the engine block and the cylinder head sealing surfaces.

    13. Notice: Clean all dirt, debris, and coolant from the engine block cylinder head bolt holes. Failure to remove all foreign material may result in damaged threads, improperly tightened fasteners or damage to components.

  13. Clean the cylinder head bolts and the engine block bolt holes.
  14. For further service to the cylinder head refer to the following:
    15. •  Cylinder Head Disassemble .
    •  Cylinder Head Cleaning and Inspection .
    •  Valve Guide Reaming, and Valve and Seat Grinding .
    •  Cylinder Head Assemble .

Installation Procedure
  1. Install the cylinder head. Refer to Cylinder Head Installation - Right Side .
  2. Install the valve push rods. Refer to Valve Rocker Arm and Push Rod Replacement .
  3. Install the exhaust manifold. Refer to Exhaust Manifold Replacement - Right Side in Engine Exhaust.

    4. Object Number: 317450 Size: SH

    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.

  4. Install the spark plug wire harness and support.

    5. Tighten
    Tighten the spark plug wire support bolts to 12 N·m (106 lb in).

  5. Install the intake manifold. Refer to Lower Intake Manifold Replacement .

    6. Object Number: 475837 Size: SH
  6. Install the stud for the generator mounting bracket.

    7. Tighten
    Tighten the generator mounting bracket stud to 20 N·m (15 lb ft).

  7. Install the generator mounting bracket. Refer to Generator Replacement in Engine Electrical.
  8. Install the bolt holding the engine wiring harness to the rear of the right cylinder head.

    9. Tighten
    Tighten the engine wiring harness bolt to 36 N·m (27 lb ft).

  9. Install the engine cooling fan. Refer to Fan Replacement in Engine Cooling.
  10. Connect the battery negative cable. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical.
  11. Install the engine cover. Refer to Engine Cover Replacement in Interior Trim.