Valve: Service and Repair

VALVE FACE
1. Using a suitable valve grinding machine, grind the valve enough to remove pits and carbon.
2. Check that the valve is ground to the correct valve face angle.
Valve face angle: 44.5°.





3. Check the valve head margin thickness.
Standard margin thickness: 0.8-1.2 mm (0.031-0.047 inch).
Minimum margin thickness: 0.5 mm (0.020 inch).
4. If the margin thickness is less than minimum, replace the valve.





VALVE LENGTH
1. Check the valve overall length.
Standard overall length:
Intake: 98.29-98.79 mm (3.8697-3.8894 inch).
Exhaust: 98.84-99.34 mm (3.8913-3.9110 inch).
Minimum overall length:
Intake: 98.19 mm (3.8657 inch).
Exhaust: 98.74 mm (3.8874 inch).

NOTE: If the overall length is less than minimum, replace the valve.

2. Check the surface of the valve stem tip for wear.





3. If the valve stem tip is worn, resurface the tip with a grinder or replace the valve.

NOTE: Do not grind off more than the minimum overall length.