Engine Repair Work Example 4

WorkKey Level: 4
NATEF Automotive Tasks: I.B.6

If the inside diameter of the guide you have measured is 0.3458” and the outside diameter of the valve stem is 0.3413”, what is the valve stem-to-valve guide clearance?

The maximum valve guide clearance is 0.0015".  Is this exhaust stem-to-valve guide clearance within service specifications?

Solution:

0.3458 – 0.3413 = 0.0045/2 = 0.00225"

This is not within specifications since 0.00225" > 0.0015".