Cylinder Head
1. Check for scratches and nicks on all gasket sealing surfaces.
2. Check for warpage.
a. Place a straightedge diagonally across the cylinder head gasket surface.
b. Slide a feeler gauge beneath the straightedge to check the head for warpage.
c. Repeat the procedure on the opposite diagonal. Discard the head if warpage is 0.006 in. (0.152 mm) or greater.
3. Check for warpage (alternate method.)
a. Use one of the CYLINDER TORQUE PLATES (Part No. HD-42324-A) in lieu of the straightedge.
b. Lay the upper plate (without vise grip) flat on the machined surface of the head.
c. As a preliminary check, see if the plate rocks from side to side. A head on which the plate rocks is immediately suspect.
d. Insert a feeler gauge between the plate and head at various locations.
e. Discard the head if warpage is 0.006 in. (0.152 mm) or greater.
4. Verify that oil passageways are open and clean.
Valve Guides
1. Inspect external surfaces, particularly the combustion chamber side, for cracks. Replace as necessary.
2. Prepare valve guides for inspection.
a. Lightly hone bore using the VALVE GUIDE HONE (Part No. B-45525).
b. Scrub with the VALVE GUIDE CLEANING BRUSH (Part No. HD-34751) to remove any dust or debris.
c. Polish the valve stem with fine emery cloth or steel wool to remove carbon buildup.
3. Check valve stem to guide clearance:
a. Carefully measure the inside diameter of the valve guide using a ball gauge.
b. Measure the outside diameter of the valve stem with a micrometer.
c. Refer to Table 3-34. If the clearance between stem and guide exceeds the limits shown, the valve stem and/or guide are excessively worn.
d. Repeat measurements with a new valve to determine if the guide must be replaced.
Valves
1. Replace the valve if there is evidence of burning or cracking.
2. Inspect the end of the valve stem for pitting or uneven wear. Replace as necessary.
3. Inspect for burrs around the valve stem keeper groove.
Remove burrs with a fine tooth file.
4. To determine if the valve stem is excessively worn, see valve guide inspection.
Valve Springs
1. Inspect springs for cracked or discolored coils. Replace as necessary.
2. Set the valve springs on a level surface. Check for proper squareness.
3. Check free length of springs using a caliper and load test using a commercially available valve spring tester. Replace springs if free length or compression force do not meet specifications. See 3.2 SPECIFICATIONS.
Tapered Keepers
Install new keepers any time valves are installed.
Valve Seats
1. Inspect seats for cracking, chipping or burning. Replace as necessary.
2. Check seats wear by measuring valve stem protrusion.
See 3.22 CYLINDER HEAD, Valve and Seat Refacing.
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