Valve Guides Valve Movement

Wobble Method





Measure the guide-to-stem clearance with a dial indicator while rocking the stem in the direction of normal thrust.
- If the measurement exceeds the service limit, recheck using a new valve.
- If the measurement is now within the service limit, reassemble using a new valve.
- If the measurement still exceeds the limit, recheck using the alternate method, then replace the valve and guide, if necessary.

Alternate Method





An alternate method of checking guide to stem clearance is to subtract the O.D. of the valve stem, measured with a micrometer, from the I.D. of the valve guide, measured with an inside micrometer or ball gauge. Take the measurements in 3 places along the valve stem and three places inside the valve guide. The difference between the largest guide measurement and the smallest stem measurement should not exceed the service limit.