F 150 2WD Pickup V8-4.6L CNG SOHC VIN 9 (1997)
Valve: Testing and Inspection
Stem to Guide Clearance
NOTE: Valve stem diameter must be within specification before checking valve stem to valve guide clearance.
1. Install Valve Stem Clearance Tool on the valve stem and install Dial Indicator with Bracketry. Lower the valve until Valve Stem Clearance Tool
contacts the upper surface of the valve guide.
2. Move the Valve Stem Clearance Tool toward the Dial Indicator and zero the Dial Indicator with Bracketry. Move the Valve Stem Clearance Tool
away from the Dial Indicator with Bracketry and note the reading. The reading will be double the valve stem to valve guide clearance. Valves with
oversize stems will need to be installed if out of specification.
