When the feeler gauge say's so. If your engine has an exhaust valve lash specification of .013”-.015” then see if a .016” feeler will slip in. If so adjustment is recommended but a little extra clearance won’t hurt and may actually benefit by allowing better valve contact with the seat to aid in cooling. Check the other end of the tolerance with a feeler .001” under the minimum too to be sure they aren’t too tight. If set accurately and tightened securely they should stay a year or longer.

Curt B.


1952 1300 Canadian 1/2 ton restomod
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