Manual:HUMMER H3 Alpha 2010Page:00373318 / 37163

Cylinder Head Cleaning and Inspection

WARNING: This page is about a different variant/trim than selected.

Special Tools

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

For equivalent regional tools, refer to Special Tools .

    Fig 1: Cleaning Carbon
    GM4957Courtesy of GENERAL MOTORS CORP.
    WARNING: Refer to Safety Glasses Warning .
    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:
    • 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.

  2. Inspect the cylinder head for the following conditions:
    1. Cracks in the exhaust ports and combustion chambers
    2. External cracks in the water chambers
    3. Gasket surfaces for excessive scratches or gouging

      Refer to Replacing Engine Gaskets .

    4. Bolt hole threads for debris or damaged threads

      Refer to Thread Repair or Thread Repair Specifications .

  3. Fig 2: Inspecting Cylinder Head For Warpage
    GM1552456Courtesy of GENERAL MOTORS CORP.
  4. Inspect the cylinder head for warpage. Refer to Engine Mechanical Specifications .
  5. Fig 3: Measuring Valve Spring Tension
    GM4960Courtesy of GENERAL MOTORS CORP.
  6. Use the J 9666:  tester in order to measure the valve spring tension. Refer to Engine Mechanical Specifications .
  7. Fig 4: Rivet-Type Plug
    GM2046466Courtesy of GENERAL MOTORS CORP.
  8. Inspect for a leaking plug (1) 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 .