Diesel Data: Automotive Repair

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. Install a new cylinder head assembly if abnormalities are found.