Outdoor Faucet Leaking Badly

I have an outdoor frost-free faucet, not sure what brand (although the handle has a plate on it that reads 'proflow'), that does more than drips. Even when I turn it off as tightly as I can, water still comes out pretty strongly. I can hear it running in the house. For now I have the inside valve turned off.

I tried changing the washer at the end of the long stem, where it actually shuts off inside the house. I don't know the terminology that well, sorry. The old washer looked bad so I figured that was the issue. After changing the problem is still the same. No amount of cranking turns off the water. I haven't changed the washer on the outside, nearer the crank. Unless I'm missing something I don't see how that one could be causing this issue that I'm having since the shutoff is almost a foot into the house.

Any help appreciated. Thanks.

Sometimes the seat is bad too.
In that case, replacing the rubber washer is not enough.

That is one reason that plumbers rarely try to fix them.
If the washer is bad, more than likely the seat is bad too.

Wow, that was quick. I do almost no plumbing, so what do you mean by the 'seat'? Does this mean that I should replace the stem assembly? Can I do that and is that type of part available? Or is the seat part of the pipe that is permanently affixed inside the house? I don't want to mess with that since I have a finished basement that would make repair pretty difficult.

The "seat" is on the faucet, and not replaceable.

Replacing the stem doesn't help.

When we replace them, we cut the wall inside.
They make plastic wall access panels that work for that.

So it looks like I would have to replace the entire assembly as you have pictured. Is this something that can be done from the outside? Does it simply screw into place with some teflon tape to seal it? I've attached a picture of the outside faucet. I'm not sure if that is the panel that you speaking of or not.

Inside the house access is nearly impossible due to my floor joists and my wall framing. An access panel wouldn't help.

Is that faucet a 1/4 turn in your picture?

On most frost free faucets, you can unthread from the outside and pull the guts out.
Then you can see what the problem is.

If a hose is left on in Winter, it can split the copper that is in the wall.
That type of leak shows up when you try to use the faucet.

I took the pic at an angle. The faucet is straight if that's what you're asking. If you're asking about how far to turn the wheel to turn it on then no, it takes several turns to turn it on full.

I've has this issue for a couple of summers now. Last winter I just turned off the valve inside. I decided to try to fix it since I had some time this weekend. I don't think I left the hose on too long a couple of winters ago but I honestly don't remember. There is not leaking inside the house. I would be able to see that.

So it sounds like I can just unscrew the whole thing from the outside. If so maybe I'll try that next weekend.