How we repair a valve guide that is loose in a Cylinder Head

This is cylinder head where the valve guide has become loose in the head and the guide hole no longer provides enough of an interference fit to securely hold the guide. Using our new State of the Art Rottler Seat and Guide machine we repair this by machining up a centering sleeve and using this to allow us to ream a larger concentric hole. We then custom machined a new guide from Ampco 45 that gives us a .04mm interference fit. The guide is cooled and the head warmed up to install the the new guide. After sizing the id to fit the valve we will recut the valve seat.