Cylinder Head Cleaning and Inspection

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Special Tools

J 8089 Carbon Removal Brush
J 9666 Valve Spring Tester

For equivalent regional tools, refer to Special Tools .

Fig 1: Cleaning Carbon

Courtesy of GENERAL MOTORS COMPANY

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.

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.
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 .

Fig 2: Inspecting Cylinder Head For Warpage

Courtesy of GENERAL MOTORS COMPANY

Inspect the cylinder head for warpage. Refer to Engine Mechanical Specifications (L83) Engine Mechanical Specifications (L86) .

Fig 3: Measuring Valve Spring Tension

Courtesy of GENERAL MOTORS COMPANY

Use the J 9666 tester in order to measure the valve spring tension. Refer to Engine Mechanical Specifications (L83) Engine Mechanical Specifications (L86) .