1. Inspect the cylinder head for out-of-flatness , using a straightedge (2) and a feeler gauge (1). If tolerances exceed 0.0508 mm (0.002 in.) replace the cylinder head.
2. Inspect the valve seats for damage. Service the valve seats as necessary.
3. Measure the valve guides for wear in three places (1,2,3). Inspect for cracks or looseness. If either condition exists replace the cylinder head.
4. Inspect push rods. Replace worn or bent push rods.
