Valve Inspection

Valve Inspection

1. Remove all carbon from the valve stems and valve heads using a wire brush.

2. Inspect each valve, install new valves if they show evidence of burn marks, warpage, scuffing, bending or valve tip spalling.

3. NOTE: The intake valve has a larger diameter.

Measure each valve stem for wear using a 0-25 mm (0-1 in) micrometer to measure valve stem diameter. Measure the valve at 2 locations 90 degrees apart. Install new valves if they are below the minimum stem diameter specifications. For additional information, refer to Specifications.

4. NOTICE: To prevent engine damage, the minimum valve margin must be maintained around the entire valve perimeter. An insufficient margin will not provide correct heat dissipation and may lead to valve warpage or breakage. Install a new valve if the margin is less than the specified minimum.

NOTE: If valve and seats are in a serviceable condition, they may be refaced to the specified angles.

Measure the valve margin at 4 locations 90 degrees apart using a dial caliper. Install new valves if they are below the minimum valve margin. For additional information, refer to Specifications.