Valve And Valve Spring
- Inspect valve stems and valve guides.
- Using a caliper gauge, measure the inside diameter of the valve guide.
Valve guide inner diameter
Intake/Exhaust:
5.500 - 5.512 mm (0.21654 - 0.21701 in.)
- Using a micrometer, measure the diameter of the valve stem.
Valve stem outer diameter
Intake: 5.465 - 5.480 mm (0.21516 - 0.21575 in.)
Exhaust: 5.458 - 5.470 mm (0.214988 - 0.21535 in.)
- Subtract the valve stem diameter measurement from the valve guide inside diameter measurement.
Valve stem-to-guide clearance
[Standard]
Intake: 0.020 - 0.047 mm (0.00078 - 0.00185 in.)
Exhaust: 0.030 - 0.054 mm (0.00118 - 0.00212 in.)
[Limit]
Intake: Less then 0.070 mm (0.00275 in.)
Exhaust: Less then 0.090 mm (0.00354 in.)
If the clearance is greater than maximum, replace the valve or cylinder head.
- Using a caliper gauge, measure the inside diameter of the valve guide.
- Inspect the valves.
- Check the valve is ground to the correct valve face angle.
- Check that the surface of the valve for wear.
If the valve face is worn, replace the valve.
- Check the valve head margin thickness.
Valve head thickness (Margin)
[Standard]
Intake: 1.02 mm (0.0401 in.)
Exhaust: 1.09 mm (0.0429 in.)
If the margin thickness is less than minimum, replace the valve.
- Check the valve length.
Valve length
[Standard]
Intake: 113.18 mm (4.4559 in.)
Exhaust: 105.79 mm (4.1650 in.)
[Limit]
Intake: 112.93 mm (4.4461 in.)
Exhaust: 105.59 mm (4.1571 in.)
- Check the surface of the valve stem tip for wear.
If the valve stem tip is worn, replace the valve.
- Inspect the valve seats
- Check the valve seat for evidence of overheating and improper contact with the valve face. Replace the cylinder head if necessary.
- Check the valve guide for wear. If the valve guide is worn, replace the cylinder head.
- Inspect the valve springs.