Valve travel
Measure the clearance between the valve stem and valve guide with a dial gauge by jiggling the valve in the valve guide.
- If the measurement exceeds the allowable limit, repeat the measurement with a new valve.
- If the measurement is now within tolerance, reassemble with a new valve.
- If the measurement is still over the limit, repeat the measurement using the other method below, then replace the valve and guide bushing if necessary.
Clearance between stem and inlet valve guide:
- Standard (new): 0.04-0.10mm
- Limit: 0.16mm
Clearance between stem and exhaust valve guide:
- Standard (new): 0.10-0.16mm
- Limit: 0.22mm
Note: An alternative way to check the clearance between the stem and guide is to subtract the outside diameter of the valve stem, measured with a micrometer, from the inside diameter of the guide, measured with a bore gauge or spherical plug gauge. Take measurements at three locations along the valve stem and at three locations inside the guide bushing. The difference between the largest dimension of the guide and the smallest dimension of the stem must not exceed the wear limit.
Clearance between stem and inlet valve guide:
- Standard (new): 0.02-0.05mm
- Limit: 0.08mm
Clearance between stem and exhaust valve guide:
- Standard (new): 0.05-0.08mm
- Limit: 0.11mm