Cylinder Head Cleaning and Inspection

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Tools Required

J 8089 Carbon Removal Brush. See Special Tools .
J 9666 Valve Spring Tester. See Special Tools .

Fig 1: Removing Carbon From Combustion Chambers

Courtesy of GENERAL MOTORS CORP.

CAUTION: Refer to Safety Glasses Caution .

IMPORTANT:

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 in order to remove the carbon from the combustion chambers. See Special Tools .
- 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 The Cylinder Head For Warpage

Courtesy of GENERAL MOTORS CORP.

Inspect the cylinder head for warpage. Refer to Engine Mechanical Specifications (RPO LY2 VIN C) or Engine Mechanical Specifications (RPO LMG VIN 0) or Engine Mechanical Specifications (RPO LY5 VIN J) or Engine Mechanical Specifications (RPO LC9 VIN 3) or Engine Mechanical Specifications (RPO L76 VIN Y) or Engine Mechanical Specifications (RPO LY6 VIN K) or Engine Mechanical Specifications (RPO L92 VIN 8) .

Fig 3: Measuring Valve Spring Tension

Courtesy of GENERAL MOTORS CORP.

Use the J 9666 in order to measure the valve spring tension. See Special Tools . Refer to Engine Mechanical Specifications (RPO LY2 VIN C) or Engine Mechanical Specifications (RPO LMG VIN 0) or Engine Mechanical Specifications (RPO LY5 VIN J) or Engine Mechanical Specifications (RPO LC9 VIN 3) or Engine Mechanical Specifications (RPO L76 VIN Y) or Engine Mechanical Specifications (RPO LY6 VIN K) or Engine Mechanical Specifications (RPO L92 VIN 8) .