Not sure what you mean by 'giving it a nip when it bottoms out'. And also what do you mean... 'If it comes undone when you undo the lever put some lock time on the thread'? Sorry I'm a total noob when it comes to this DIY talk lol
A nip is a bit of a turn with a spanner, enough to lock off, not enough to smash the lever handle.
Yeah locktite....stoopid iPad autocorrect.