Valve Guide Clearance
WARNING: This page is about a different car, the 2020 Infiniti QX60. However, it is still accessible from the selected car via links, so may be relevant.
- Measure valve deflection as shown, below. (Valve and valve guide mostly wear in this direction.)
Valve deflection limit (dial gauge reading)
Intake
: 0.24 mm (0.0094 in)
Exhaust
: 0.28 mm (0.0110 in)
- If it exceeds the limit, check valve to valve guide clearance.
- Measure valve stem diameter and valve guide inner diameter. Refer to Cylinder Head .
- Check that clearance is within specification.
(Valve guide clearance) = (Valve guide inner diameter) - (Valve stem diameter)
Valve to valve guide clearance standard
Intake
: 0.020 - 0.053 mm (0.0008 - 0.0021 in)
Exhaust
: 0.040 - 0.073 mm (0.0016 - 0.0029 in)
Valve to valve guide clearance limit
Intake
: 0.08 mm (0.0031 in)
Exhaust
: 0.1 mm (0.004 in)
- If it exceeds the limit, replace valve or valve guide.