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.
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. | 
 
| •  | Valve stems and heads on a buffing wheel | 
 
|    | Remove all dirt, debris, or threadlocking material from the bolt holes. | 
 
- Inspect the cylinder head for the following conditions:
 
| 2.1.  | Cracks in the exhaust ports and combustion chambers | 
 
| 2.2.  | External cracks in the water chambers | 
 
- Inspect the cylinder head for warpage. Refer to 
Engine Mechanical Specifications.
 
- Use the 
J 9666 tester
 in order to measure the valve spring tension.
Refer to 
Engine Mechanical Specifications.
 
- 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.