Operation CHARM: Car repair manuals for everyone.

Valve Guide

Valve-Stem to Valve Guide Clearance





Special Tool(s)

NOTE: Valve stem diameter must be within specifications before checking valve stem to valve guide clearance.





1. NOTE: If necessary, use a magnetic base.

Install a Valve Stem Clearance Tool on the valve stem and install a Dial Indicator with Bracketry. Lower the valve until the Valve Stem Clearance Tool contacts the upper surface of the valve guide.
2. Move the Valve Stem Clearance Tool toward the indicator and zero the indicator. Move the Valve Stem Clearance Tool away from the indicator 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.

Valve-Guide Inner Diameter





1. Measure the inner diameter of the valve guides in two directions where indicated.

2. If the valve guide is not within specifications, ream the valve guide and install a valve with an oversize stem or remove the valve guide and install a new valve guide.

Valve-Guide Reaming





1. Use a hand-reaming kit to ream the valve guide.
2. Reface the valve seat.
3. Clean the sharp edges left by reaming.