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Valve Guide Inner Diameter

NOTE: Refer to the appropriate Engine article for the specification.

NOTE: Valve guides tend to wear in an hourglass pattern. The ball gauge can be inserted into the combustion chamber side of the valve guide, if necessary.

1.
Use a ball gauge to determine the inside diameter of the valve guides in 2 directions at the top, middle and bottom of the valve guide.

GFD32811

Courtesy of FORD MOTOR COMPANY

2.

Measure the ball gauge with a micrometer.

GFD32812

Courtesy of FORD MOTOR COMPANY

3.

If the valve guide is not within specifications, install a new cylinder head assembly.