Replacing Valve Guides
by Scott Suhring
While rebuilding my ’59 TR3A engine, the machine shop that boiled and tested the head for straightness recommended that the exhaust valve guides be replaced. Reading the manual, it instructs you to lay the head on your bench, gasket side down, and using an appropriate drift, drive the guide down through the head. Well, this does not work well for an engine that is over 40 years old and the guides are quite set in their sleeves. Sitting and thinking about this for a while, I came to the conclusion that I needed a way to apply a good amount of force to the sleeve while maintaining the vertical alignment so as not to break the top of the sleeve that is exposed above the head (don’t ask how I know).
The solution was the purchase of 2 bolts: one that was the same size as the inner diameter of the sleeve and the other with the same or near to same outer diameter of the sleeve (in my case, 3/8" and 1/2"). The length of the bolt is not critical, but I used 4" bolts. Next, cut off the threaded part of the bolt so you only have the smooth shaft. I would recommend filing the end so that it is level for the bolt used for tapping down the outer diameter. Use these steps:
Worked like a charm!
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