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For 1990-2009 cars only

Cylinder Head Cleaning and Inspection 6.2L LS9

Special Tools

    • J 8089 Carbon Removal Brush
    • J 9666 Valve Spring Tester
         For equivalent regional tools, refer to Special Tools

    Warning: Refer to Safety Glasses Warning in the Preface section.


    Object Number: 4957  Size: SH

    Note: 

       • When cleaning a cylinder head in a thermal type oven, do not exceed 204°C (400°F).
       • Be careful not to scuff the chamber.

  1. Clean the following components:
  2. • Use the J 8089 Brush in order to remove the carbon from the combustion chambers.
    • Gasket surfaces
      Refer to Replacing Engine Gaskets.
    • Valve stems and heads on a buffing wheel
    • Bolt hole threads
      Remove all dirt, debris, or threadlocking material from the bolt holes.
  3. Inspect the cylinder head for the following conditions:
  4. 2.1. Cracks in the exhaust ports and combustion chambers
    2.2. External cracks in the water chambers
    2.3. Gasket surfaces for excessive scratches or gouging

    Refer to Replacing Engine Gaskets.

    2.4. Bolt hole threads for debris or damaged threads

    Refer to Thread Repair or Thread Repair Specifications.


    Object Number: 1552456  Size: SH
  5. Inspect the cylinder head for warpage. Refer to Engine Mechanical Specifications.

  6. Object Number: 2085664  Size: SH
  7. Cylinder heads that have excessive warpage or a damaged sealing surface can be machined as required. Determine the cylinder head thickness as measured from the cast in place machining pads (1 and 2) to the head deck sealing surface. A cylinder head that measures less than 6.88-7.12 mm (0.271-0.283 in) (a) cannot be machined and must be replaced.

  8. Object Number: 4960  Size: SH
  9. Use the J 9666 Tester in order to measure the valve spring tension. Refer to Engine Mechanical Specifications.

  10. Object Number: 2046466  Size: SH
  11. Inspect for a leaking plug. Production applications use a rivet-type plug at the top rear coolant passage of each cylinder head. If service of a leaking plug is required, it is necessary to remove the cylinder head from the engine to properly remove the plug. Refer to Cylinder Head Disassemble

Cylinder Head Cleaning and Inspection 6.2L LS3

Special Tools

    • J 8089 Carbon Removal Brush
    • J 9666 Valve Spring Tester

    Warning: Refer to Safety Glasses Warning in the Preface section.


    Object Number: 4957  Size: SH

    Note: 

       • When cleaning a cylinder head in a thermal type oven, do not exceed 204°C (400°F).
       • Be careful not to scuff the chamber.

  1. Clean the following components:
  2. • Use the J 8089 brush in order to remove the carbon from the combustion chambers.
    • Gasket surfaces
      Refer to Replacing Engine Gaskets.
    • Valve stems and heads on a buffing wheel
    • Bolt hole threads
      Remove all dirt, debris, or threadlocking material from the bolt holes.
  3. Inspect the cylinder head for the following conditions:
  4. 2.1. Cracks in the exhaust ports and combustion chambers
    2.2. External cracks in the water chambers
    2.3. Gasket surfaces for excessive scratches or gouging

    Refer to Replacing Engine Gaskets.

    2.4. Bolt hole threads for debris or damaged threads

    Refer to Thread Repair or Thread Repair Specifications.


    Object Number: 1552456  Size: SH
  5. Inspect the cylinder head for warpage. Refer to Engine Mechanical Specifications.

  6. Object Number: 4960  Size: SH
  7. Use the J 9666 tester in order to measure the valve spring tension. Refer to Engine Mechanical Specifications.

  8. Object Number: 2046466  Size: SH
  9. Inspect for a leaking plug. Second design applications use a rivet-type plug at the top rear coolant passage of each cylinder head. If service of a leaking plug is required, it is necessary to remove the cylinder head from the engine to properly remove the plug. Refer to Cylinder Head Disassemble

Cylinder Head Cleaning and Inspection 7.0L

Special Tools

    • J 8089 Carbon Removal Brush
    • J 9666 Valve Spring Tester

For equivalent regional tools, refer to Special Tools

    Warning: Refer to Safety Glasses Warning in the Preface section.


    Object Number: 4957  Size: SH

    Caution: Do not clean titanium components with chlorinated solvents. Brake parts, and similar cleaning solvents, safety solvents, or refrigerant that contains chlorofluorocarbons (CFCs) should not be used. Using chlorinated solvents to clean titanium components can result in component damage, leading to stress corrosion cracking that may be undetected with normal visual inspection. Acceptable materials for cleaning titanium components include non-chlorinated solvents, alcohol, acetone, and methanol.

    Note: 

       • When cleaning a cylinder head in a thermal type oven, do not exceed 204°C (400°F).
       • Be careful not to scuff the chamber.

  1. Clean the following components:
  2. • Use the J 8089 J 8089 brush in order to remove the carbon from the combustion chambers.
    • Gasket surfaces
    • Refer to Replacing Engine Gaskets.
    • Valve stems and heads
    • Refer to Adhesives, Fluids, Lubricants, and Sealers.
    • Bolt hole threads
    • Remove all dirt, debris, or threadlocking material from the bolt holes.
  3. Inspect the cylinder head for the following conditions:
  4. 2.1. Cracks in the exhaust ports and combustion chambers
    2.2. External cracks in the water chambers
    2.3. Gasket surfaces for excessive scratches or gouging

    Refer to Replacing Engine Gaskets.

    2.4. Bolt hole threads for debris or damaged threads

    Refer to Thread Repair or Thread Repair Specifications.


    Object Number: 1552456  Size: SH
  5. Inspect the cylinder head for warpage. Refer to Engine Mechanical Specifications.

  6. Object Number: 4960  Size: SH
  7. Use the J 9666 tester in order to measure the valve spring tension. Refer to Engine Mechanical Specifications.

  8. Object Number: 2046466  Size: SH
  9. Inspect for a leaking plug. Second design applications use a rivet-type plug at the top rear coolant passage of each cylinder head. If service of a leaking plug is required, it is necessary to remove the cylinder head from the engine to properly remove the plug. Refer to Cylinder Head Disassemble