The 14-day rule--or length of stay limit--is going to vary by jurisdiction, although it is mostly 14-days. It always pays to check with the local land manager to clarify this. In many cases I've found that the land manager is either unaware of the rule or just doesn't care--and will tell you that. In other cases I've seen them come out and cite people on day 15.
As said, potable water is going to be the biggest single determinant of how long you can dry camp without replenishment. Some people come on here and ask about methods and equipment for purifying water from nearby streams or even ponds. I recommend against this, and I've done a lot of it when backpacking in actual wilderness. The problem is that any water source that has been accessed by other humans has been used as a toilet already. The more people, the more toilets. The more toilets, the more time and equipment required to purify. It ultimately becomes quicker to drive an hour or two and buy bottled water, which is what I do.
Regarding generator hours, there are no generator hours outside of established campgrounds. There is common courtesy for others, but no law to say that you can't run your generator all night on NFS or BLM land that is not otherwise posted for camping.
In the west it is fairly easy to finding boondocking spots where there are no neighbors nearby, and nowhere near a campground where such hours would apply even if you are alone, or own a "quiet" generator. Out in these desolate places you are free to do as you please.
My general advice is to always carry heavy clothing, even in summer, and extra food and bottled water, apart from you water tank. Most of us stay aware of whether we have cell phone service, and some of us carry portable sat communicators like the Delorme Inreach. And some are also licensed to carry weapons.
Regarding animal attacks, when tenting alone near the John Muir trail in sierras, I had a large black bear tear down my food bag and happily eat everything I owned while I stood there shouting and banging pots at him. My feeling of helplessness in this encounter is why I now pay so much attention to the issues in my previous paragraph.