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Setting valve clearance O-290

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Dana

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I need to check/adjust the valve clearance on my O-290-D (solid lifters, supposed to be checked every 100 hours) and have two stupid questions. The Lycoming manual says:

“0-235, 0-290D Series - Be sure that the piston is at top center compression stroke and that both valves are closed. Assemble adjusting screw in valve rockers and using clearance gage adjust thec learance between the valve tip and valve rocker. Adjust in the following manner:

Set tappets with .007 in. - .009 in. clearance cold. Recheck tappet clearance after run-in, clearance should be from .006 in. to .012 in. After adjusting, lock the adjusting screw in place with the locknut.”


Does that mean that if the initial clearance is between .006-.012 I should leave it alone, or should I still set it to .007-.009?


Does “recheck after run-in” only apply to newly overhauled engines or cylinders, or are you supposed to set the valves, run the engine, and then remove the valve covers and recheck every time you set them at 100 hours?
 

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