Valve Guide Clearance

WARNING: This page is about a different car, the 2003 Nissan Altima. However, it is still accessible from the selected car via links, so may be relevant.

Perform this inspection before removing the valve guide.

Make sure that the valve stem diameter is within the specification.
Push the valve out by approximately 15 mm (0.59 in) toward the combustion chamber side to measure the valve's runout volume (in the direction of dial gauge) with dial gauge.
Half of the runout volume accounts for the valve guide clearance.
1. Intake
2. runout :0.020 - 0.053 mm (0.0008 - 0.0021 in) or less
3. Exhaust
4. runout :0.030 - 0.063 mm (0.0012 - 0.0025 in) or less
Fig 1: Checking Valve Runout
Courtesy of NISSAN MOTOR CO., U.S.A.