For 1990-2009 cars

#### 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.

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:

2.1. | Cracks in the exhaust ports and combustion chambers

2.2. | External cracks in the water chambers

2.3. | Gasket surfaces for excessive scratches or gouging

Refer to Replacing Engine Gaskets.

2.4. | 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.
4. Use the J 9666 tester in order to measure the valve spring tension. Refer to Engine Mechanical Specifications.
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. Refer to Cylinder Head Disassemble.