For 1990-2009 cars

#### Tools Required

• | J 8089 Carbon Removal Brush

• | J 9666 Valve Spring Tester

1. Use the J 8089 to clean the carbon from the combustion chambers and from the valves.
2. Clean the valve guides.
3. Use a buffing wheel to clean the valve stems and valve heads.
4. Clean the cylinder head.
5. Clean the engine block gasket surfaces.
6. Clean the bolt hole threads in the cylinder heads and in the engine block.
7. Cracks in the cylinder head usually occur between the exhaust valves or between the exhaust valve and the spark plug hole. Inspect for the following in the cylinder head:

• | Cracks in the exhaust ports

• | Cracks in the combustion chambers

• | Cracks to the water jackets

8. Inspect the valves for the following:

• | Burned heads (1)

• | Cracked faces (2)

• | Bent stems (3)

• | Damaged stems (4)

9. Inspect the valve seats for cracks.
10. Inspect the valve seats for looseness.
11. Perform the following steps to inspect the valve springs for squareness:

• | Place the valve spring on a level surface next to a square.

• | Rotate the valve spring.

• | Replace the valve spring if the valve spring is more than 1.58 mm (0.062 in) out of square.

12. Use J 9666 to inspect the valve spring tension.
13. Replace the valve spring if the spring length is less than 34 mm (1.338 in) when compressed at 250 N (56.6 lb).