For 1990-2009 cars

#### Tools Required

• | J 8089 Carbon Removal Brush

• | J 9666 Valve Spring Tester

• | J 8001 Dial Indicator Set

### Cleaning Procedure

Caution: Refer to Safety Glasses Caution in the Preface section.

Important: Mark, sort, or organize components for return to their original locations.

1. Clean the valve stems and heads on a buffing wheel.
2. Clean the following components in solvent:

• | Valve stem keys (220)

• | Valve spring cap (219)

• | Valve spring (218)

• | Valve Rotators (216)

• | Valve (232)

• | Cylinder head

Caution: Refer to Safety Glasses Caution in the Preface section.

3. Dry the components with compressed air.

Important: Do not damage the chamber or the valve seat.

4. Use the J 8089 in order to clean the carbon from the combustion chambers.

### Visual Inspection Procedure

Inspect the cylinder head for the following conditions:

• | Damaged gasket surfaces

• | Damage to threaded bolt holes

• | Burnt or eroded areas in the combustion chamber

• | Cracks in the exhaust ports and combustion chambers

• | External cracks in the water chamber

• | Restrictions in the intake or exhaust passages

• | Restrictions in the cooling system passages

### Flatness Measurement Procedure

1. Measure the cylinder head for warpage with a straight edge and feeler gage.

• | A cylinder head block deck with warpage in excess of 0.050 mm (0.002 in) within a 150.0 mm (6.0 in) area must be repaired or replaced.

• | A cylinder head exhaust manifold deck with an overall warpage in excess of 0.102 mm (0.004 in) must be repaired or replaced.

• | A cylinder head intake manifold deck with warpage in excess of 0.080 mm (0.003 in) must be repaired or replaced.

2. A cylinder head block deck can be resurfaced up to 0.305 mm (0.012 in) maximum removal.

Important: Excessive cylinder head resurfacing will affect compression ratio and emission control.

3. A cylinder head that requires excessive resurfacing must be replaced.

### Valve Inspection Procedure

1. Inspect the valves for the following conditions:

• | Burnt or damaged areas (1)

• | Undersized valve margin (2)

• | Bent stem (3)

• | Scoring or other damage to the stem (4)

• | Worn key groove (5)

• | Worn stem tip (6)

2. Inspect the valve contact surface for the following conditions:

• | Undersized margin (1)

• | Pitted surface (2)

• | Burnt or eroded areas (3)

• | Acceptable edge, margin (4)

Important: Minor imperfections of the valve may be corrected during reconditioning.

3. Valves with excessive damage must be replaced.

### Valve Spring Inspection and Measurement

1. Inspect the valve springs for broken coils or coil ends.
2. Use the J 9666 in order to measure the valve spring force. Refer to Engine Mechanical Specifications .

Important: Add a maximum of 1 shim, up to 0.726 mm (0.030 in) thick, to increase tension.

3. If the valve spring tension is low, use a shim to increase tension.
4. Inspect the valve spring tension again. A valve spring that does not meet specification must be replaced.

### Valve Guide Measurement Procedure

Important: Excessive valve stem-to-guide clearance may cause an excessive oil consumption and may also cause a valve to break. Insufficient clearance results in noisy and sticky functioning of the valve and disturbs the engine assembly smoothness.

1. Measure the valve stem-to-guide clearance.

1.1. | Clamp the J 8001 on the exhaust port side of the cylinder head.

| Important: The indicator stem must contact the side of the valve stem just above the valve guide.

1.2. | Locate the indicator so that the movement of the valve stem from side to side, crosswise to the cylinder head, causes a direct movement of the indicator stem.

1.3. | Drop the valve head approximately 1.6 mm (0.064 in) off the valve seat.

1.4. | Use light pressure when moving the valve stem from side to side in order to obtain a clearance reading. Refer to Engine Mechanical Specifications .

2. Valve guide (2) with excessive clearance must be repaired. Refer to Valve Guide Reaming, and Valve and Seat Grinding .
3. Replace the cylinder head if the valve guide cannot be repaired or reamed to accept an oversize valve stem.