[Walt Fricke]

While I don't think the Nylocs hurt anything, neither do I think they help. I've never seen one of these case bolt nuts back off. Have any of you seen that? I suppose if the builder spun the nuts on by hand, and then missed getting a wrench on one of them, it could fall off. But that doesn't seem like something a change of nut type would help much. And I suspect that one of the 22 or so nuts missing would not lead to a leak, eithr, though I don't volunteer to test this.

Proper application of the sealant, so it surrounds the stud holes on the case halves, should prevent any oil at all migrating to and along the studs to get past the nuts/washers. I've not seen weeping there (other than that pesky IS stud, but that is a special case and it is not a periphery stud).

Valve covers are different.