48. Cylinder Head Cleaning and Inspection
Cylinder Head Cleaning and Inspection
Special Tools
* J 8089 - Carbon Removal Brush
* J 9666 - Valve Spring Tester
For equivalent regional tools, refer to Special Tools Tools and Equipment
Warning:
Refer to Safety Glasses Warning 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 - brushin order to remove the carbon from the combustion chambers.
* Gasket surfaces
Refer to Replacing Engine Gaskets 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 Replacing Engine Gaskets.
4. Bolt hole threads for debris or damaged threads
Refer to Thread Repair or Thread Repair Specifications.
3. Inspect the cylinder head for warpage. Refer to Engine Mechanical Specifications (RPO L96 VIN G) Service Limits & General Specifications (RPO L96 VIN G)Engine Mechanical Specifications (RPO LMF VIN 4) Service Limits & General Specifications (RPO LMF VIN 4)Engine Mechanical Specifications (RPO L20 VIN A) Service Limits & General Specifications (RPO L20 VIN A).
4. Use the J 9666 - testerin order to measure the valve spring tension. Refer to Engine Mechanical Specifications (RPO L96 VIN G) Service Limits & General Specifications (RPO L96 VIN G)Engine Mechanical Specifications (RPO LMF VIN 4) Service Limits & General Specifications (RPO LMF VIN 4)Engine Mechanical Specifications (RPO L20 VIN A) Service Limits & General Specifications (RPO L20 VIN A).
5. Inspect for a leaking plug (1). 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.