Valve Guide Inner Diameter

General Procedure 

• 1.
  
  
  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.

  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.

Courtesy of FORD MOTOR COMPANY

• 2.
  
  Measure the ball gauge with a micrometer.

Courtesy of FORD MOTOR COMPANY

• 3.
  
  If the valve guide is not within specifications, install a new cylinder head assembly.