Scraping the crud away, I've had a better look at my crankcase casting & the left front stud hole runs into the interior. I might redo that one come oil change day. Judging by this example no other holes could be open on any similar casting, which I presume means all of them?
Bob,
I did this with the motor in the bike. One stud had iffy threads and would not work with the 2 nuts method.
I had to weld a nut on the stud and got it out that way.
4 new studs and seal on all threads and no more leaks. 2 years.
