Valve Guide: Service and Repair

Measure valve stem diameter in 3 places, top, center and bottom, noting that exhaust valve stems are approximately .001 inch larger at top of stem than at the bottom. Measure valve guide bore with gauge and compare with valve stem diameter to obtain clearance. If clearance is not within specifications, replace valves and/or ream valve guide bores as needed. Valves are available in standard size and .003 inch and .005 inch oversize.