Tools Required

1. Inspect the cylinder head gasket and the mating surfaces. Inspect for leaks, corrosion and blowby.
2. If the gasket failed, determine the cause. Gasket failure is caused by the following conditions:

•	Improper installation

•	A loose or warped cylinder head

•	Missing dowel pins

3. Clean the cylinder head. Remove all foreign material to the bare metal. Do not use a motorized wire brush on any gasket sealing surface.
4. Clean the threaded holes.
5. Clean the remains of the sealer from the threaded holes.
6. Inspect the cylinder head for cracks. Inspect between the valve seats. Inspect inside of the exhaust ports.

Important: Do not attempt to weld the cylinder head. If the cylinder head is damaged, replace the cylinder head.

7. Inspect the cylinder head deck for corrosion.



8. Inspect the following locations for flatness:

•	The cylinder head deck

•	The intake manifold mating surfaces

•	The exhaust manifold mating surfaces

•	Recondition the surfaces by parallel grinding. Replace the cylinder head if you must remove more than 0.254 mm (0.010 in).




9. Measure the height from the deck surface to the cast pads. Do this in order to determine if the cylinder head has sufficient deck surface thickness to resurface.

New cylinder heads measure from 1.372-1.676 mm (0.054-0.066 in). If the cylinder head does not meet the minimum thickness after resurfacing, replace the cylinder head.

10. Inspect all of the threaded holes for damage. If necessary, repair the threaded holes.
11. Inspect the seating surfaces. Inspect the cooling jacket plugs.
12. Clean the valve guides. Inspect the valve guides for wear.
13. Inspect the valve seats for excessive wear and burned spots.

Recondition the valve seats by grinding. Use an oscillating type valve seat grinder. Follow the grinder manufacturer's instructions. If the valve seat is too wide after grinding, use a 20 degree stone or a 70 degree stone in order to narrow the valve seat. The 20 degree stone will lower the seat. The 70 degree stone will raise the seat. Replace or recondition the valves if the seats are reconditioned.

Notice: Clean the valve guides before reaming. Packing of chips or carbon may result in the reamer jamming into the valve guide or broken reamer flutes.

14. Clean any foreign material from the valves. Use a wire brush in order to remove carbon. Do not scratch the valve stem with the wire brush. Soak the valves in carburetor cleaning fluid in order to remove varnish.
15. Use a suitable tool in order to clean the valve guides.
16. Inspect the valve stem tip for wear. Recondition the valve stem tip by grinding.
17. Follow the grinder manufacturer's instructions. Ensure that the new surface is perpendicular to the valve stem.
18. Inspect the valve key for chipped or worn lands. Replace the valve if the valve key groove is damaged.
19. Inspect the valve face for burning or cracking. If pieces of the valve face are broken off, inspect the corresponding piston and cylinder head area for damage.
20. Inspect the valve stem for burrs and scratches. Use an oil stone in order to remove burrs and minor scratches.
21. Inspect the valve stem for straightness. Use V blocks in order to inspect the valve head for bending or distortion. Replace any bent or distorted valves.
22. Inspect the valve face for grooving. If the groove is so deep that refacing the valve face would result in a knife edge, replace the valve.



23. After grinding the valves, measure the valve margin. Replace the valve if the margin is less than the minimum recommended margin.



24. Measure the valve movement:

24.1.

Insert the valve into the guide.

24.2.

Lift the valve 2 mm (1/8 in) off of the seat.

24.3.

Move the valve from side to side.

24.4.

Use a dial indicator in order to measure the amount of movement.





Important: Clean the valve guide before reaming. In order to avoid breaking the reamer flutes, do not push down on the reamer.

25. Clean and lubricate the reamer often during use.



26. Inspect the valve springs expanded height.
27. Inspect the spring ends. If the spring ends are not parallel, the spring is bent. Replace the bent spring.



28. Inspect the spring load. If the spring load is below specification, replace the spring.
29. Inspect the valve spring seating surface of the spring retainers for wear or gouging. If the seating surface is damaged, replace the spring retainers.
30. Use the following procedure to measure the valve seat concentricity:

30.1.

Lift the valve off its seat.

30.2.

Apply a dab of Prussian blue to the valve face.

30.3.

Seat and rotate the valve.

The Prussian blue traces transferred to the valve seat are an indication of concentricity of the valve seat.

31. Use the following procedure in order to measure the valve runout:

31.1.

Clean the Prussian blue off.

31.2.

Apply a dab of Prussian blue to the valve seat.

31.3.

Seat and rotate the valve.

The traces of Prussian blue transferred to the valve indicates valve runout

31.4.

Recondition the valve seat or valve face if needed.