If an older engine is running
If an older engine is running fine I really try to avoid scaring the owner when possible, however when they just come out and ask as you have I think it's best to give the facts that the sodioum valves are certianly capable of breaking off without warning or reason.
IMO the guide to stem rocking that occurs, along with the embrittlement of the stem to head area is as much or more of the culprit than valve adjustment.
Sorry.
If an older engine is running fine I really try to avoid scaring the owner when possible, however when they just come out and ask as you have I think it's best to give the facts that the sodioum valves are certianly capable of breaking off without warning or reason.
IMO the guide to stem rocking that occurs, along with the embrittlement of the stem to head area is as much or more of the culprit than valve adjustment.
Sorry.