2. Pull the valve approximately 10mm out of its guide, then measure the clearance between the valve stem and guide with a dial gauge while rocking the stem in a perpendicular direction (swing method).
If the measurement result exceeds the working limit, repeat it again using a new valve.
If the measurement is now within the operating range, reassemble the assembly using a new valve.
If the measurement result still exceeds the operating limit, go to step 3.
Clearance between intake valve stem and guide bushing:
- Standard (new): 0.04—0.10 mm.
- Working range: 0.16 mm.
Clearance between exhaust valve stem and guide sleeve:
- Standard (new): 0.10-0.16 mm.
- Working limit: 0.22mm.
3. Subtract the outer diameter of the valve stem (measured with a micrometer) from the inside diameter of the guide bush (measured with an internal micrometer or ball meter).
Take measurements at three locations along the length of the valve stem and at three locations inside the valve guide.
The difference between the largest guide bush diameter measurement and the smallest valve stem diameter measurement must not exceed the operating limit.
Clearance between intake valve stem and guide bushing:
- Standard (new): 0.020—0.050 mm.
- Working limit: 0.08mm.
Clearance between exhaust valve stem and guide sleeve:
- Standard (new): 0.050—0.080 mm.
- Working limit: 0.11mm.