I opened an outside electric box that supplies power to my fountain. The GFI appeared to have failed. When I pulled the pump motor plug the plug was melted to the GCFI and the GFCI had a burn hole in it. As I removed the 3 wires I strted to notice some funky wire match ups. The whire wire aws attached to the load side of the GFCI. The red wire was attached to where th white should be on a GFCI and the black wire was attached to the green ground screw. Kepp in mind this had worked for 5 years. As I pulled the wires I found 121 v on the red and zero on the white, them found 91 volts on the black. Brought in a new known ground directly from the panel and measure to that. Red to ground= 121 v, white to ground=0 v and black to ground= 13 v. I switch the white and red back and forth on the two terminals and always get a reading on mytester that the nuetral and hot are reversed. This is just driving me nuts and starting to tick me since I used to be retty good with this. Who out there can enlighten me on my wiring?

OK, sounds like white is ground. Red is HOT and black is neutral.

Which means it would register as neutral and ground reversed. The GFCI should have picked up on this.

The 13 V bothers me a bit:

Were you holding the wire with your finger?
Where is the black connected in the panel?
Is the panel a sub-panel?
... If it is, is the neutral and ground separate?

My best guess is red is hot and white is neutral carrying zero volts on all tests. The black measured 13v to a known separate ground and 91 v when measured to the hite. This is confusing since I can't trace the wires back to the panel. Somewhere someone has installed an old junction somewhere inside the house. There are no reds in the panel but I have one outside. I am thinking of installing a new GFCI to red/hot and white/neutral just to get a working circuit. This would leave me with no ground but at least GFCI protection. What do you see as the pros/cons to this. The fact that black is carrying some voltage is goofy to me. The old GFCI had the black going to the green ground screw. Who ever wired this circuit was no pro apparently and the hole burned in the GFCI tells me what was working has stopped working. Any advice will be appreciated. Bob PS no sub panel and the wires where hanging in the ar when I touched them with my multimeter.

There may be something in series on that black lead, however since the voltage measurements are so stable, it most likely is something purely resistive or inductive, not a light bulb. Look for a 12v landscape lighting transformer somewhere. With that wiring fiasco I wouldn't put it past someone to have gotten a low voltage circuit mixed into things.

If you have access to a 'fox and hound', find the breaker(s) and turn the line in question off. Then put the fox on one conductor of the mystery cable and your separate new ground conductor. You may be able to find things easier that way. I just did that on a circuit yesterday and found a switch that nobody had any idea what it did. It's effect was to shut off a whole room in an unrelated area of the house!

Regardless, spend the time to fix that mess. You can't let it for some other innocent to deal with later.

Good luck. I'd love to hear what you find.