> anyway, they always (AFAIK) break at the threaded end.  The RTV will
> prevent the bolt from backing out.
>  

RTV sets by evaporating a carrier, doesn't it?  How would it cure in an
airtight bolt hole?  Is it supposed to be allowed to cure before the
bolt is inserted?

I'm reasonably certain that RTV (silicone) cures by absorbing moisture from
the air.

Al