Valve and Valve Seat

Valve-Stem Diameter





1. Measure the diameter of each intake and exhaust valve stem at the points shown. Verify the diameter is within specification.
- If out of specification, install new components as necessary.

Valve-Inspection





1. Inspect the following valve areas:
1 the end of the stem for grooves or scoring
2 the valve face and the edge for pits, grooves or scores
3 the valve head for signs of burning. erosion, warpage and cracking
4 the valve margin for wear

Valve-Seat Inspection

Valve and Seat Refacing Measurements

CAUTION: After grinding valves or valve seats, check valve clearance.





1. Check the valve head and seat.
- Check valve angles.
- Check margin width.
- Be sure margin width is within specification.
2. Inspect for abnormalities on the valve face and seat.

Valve-Seat Width





1. Measure the valve seat width. If necessary, grind the valve seat to specification.
- Measure the intake valve seat width.
- Measure the exhaust valve seat width.
- Recheck the valve spring installed length after the seats have been ground, and shim the valve springs as necessary to achieve the correct installed spring length.

Valve-Seat Runout





1. Use the Valve Seat Runout Gauge to check valve seat runout.