Section lines don't easily stick to the centres of holes or bores. That's pity.
Maybe I'm missing a trick? but I was dropping a point on a hidden layer in the centre of the relevant hole/bore and making my line coincident with that.
Since we got the easier to create sections in 2014 (?) it seems the section line snaps to the centre of circular features, and of course my method above becomes more onerous...
BUT even though it seemed to snap to the circle centre the section position is not constrained!
In your section view when you apply a diameter it automatically inserts the <mod-diam><dim> in the dimension.
But Beware, if you move circular feature the section doesn't follow, and its a disaster what happens to that diameter dim if you don't realise!!
Although it keeps the diameter symbol, it becomes a linear dimension to the sectioned edge, but retains the diameter symbol.
See below, when the section is off, the hole diameter dimension changes.
Surely I am missing some trick to constrain the section to the circular centre to avoid this issue?
50 odd parts to re-drill today anyway :(