Cylinder Head and Gasket Surface Clean and Inspect

1. Remove spark plugs.
2. Inspect cylinder head gasket and mating surfaces for leaks, corrosion and blow-by. If gasket has failed, use following faults to determine cause:
- Improper installation
- Loose or warped cylinder head
- Missing, off location or not fully seated dowel pins
- Corrosion in seal area around the coolant passages
- Chips or debris in cylinder head bolt holes
- Bolt holes in cylinder block not drilled or tapped deep enough
- Other





3. Inspect cylinder head gasket surface.
- Cylinder head may be reused if corrosion is found only outside a 4 mm (0.375 inch) band around each combustion chamber (1).
- Replace cylinder head if the area between valve seats is cracked (2).
- Replace cylinder head if corrosion has been found inside a 4 mm (0.375 inch) band around each combustion chamber (3).
4. Clean cylinder head bolts.

IMPORTANT: Do not use a wire brush on any gasket sealing surface.

5. Clean cylinder head. Remove all varnish, soot and carbon to bare metal.
6. Clean valve guides.
7. Clean threaded holes. Use a nylon bristle brush.
8. Clean remains of sealer from plug holes.
9. Inspect cylinder head bolts for damaged threads or stretching and damaged heads caused by improper use of tools.
10. Replace all suspect bolts.
11. Inspect cylinder head for cracks. Check between valve seats and exhaust ports.

IMPORTANT: Do not attempt to weld cylinder head, replace it. If cracked, it must be replaced.

12. Inspect the cylinder head deck for corrosion, sand inclusions and blow holes.





13. Inspect intake and exhaust manifold mating surfaces for flatness. These surfaces may be reconditioned by parallel grinding.
14. Use following steps to determine the amount of reconditioning needed:
- If warpage is less than 0.010 mm (0.00039 inch), reuse the cylinder head but do not resurface.
- If warpage is between 0.010 mm (0.00039 inch) and 0.100 mm (0.0039 inch), resurface the cylinder head before reusing.
- If warpage is over 0.100 mm (0.0039 inch), discard cylinder head.
15. Inspect all threaded holes for damage. Threads may be reconditioned with thread inserts.
16. Inspect sealing surfaces.





17. Inspect cylinder head plugs.