I know this is wrong and I’m going to eventually hire an electrician but the electrician is going to want to—and need to—correct way more that just that problem and I can’t afford it right now. Meanwhile, I want to use the power in my garage. The power seems to work fine and worked for the prior owner but a guy wire as neutral just seems crazy.

A lot of the wiring in the house is old copper two wire no gnd, probably 10 gauge and where spiced it’s a soldered splice, which I guess was state of the art back in the day. The power from the house is 12 gauge two wire with no ground wire. The hot/black wire is connected with a Wirenut to a black wire that’s supported by a guy wire and runs overhead to the garage 50 feet away. The neutral/white wire is connected to the guy wire. (By the way, there’s a lengthy but wonderful thread entitled “So why is it bad to have the ground carry the neutral load?”) At the garage there’s regular Romex® (or Romex like) 12/2 +Gnd NM coming out of a metal conduit near the garage roof with the black Romex wire connected to the overhead black wire and the white Romex wire connected to the guy wire. The Romex runs down the conduit into a subpanel in the garage. The subpanel has a single 20 amp fuse. The white Romex wire and the Romex ground wire are connected to the bus bar, which seems correct—except that the bus bar isn’t grounded.

For my temporary fix I planned to add a real wire to replace using the guy wire as neutral. I have 12 solid THHN for that. It seemed like a good temporary fix until I started thinking about the lack of grounding of the sub panel. Should I drive a re-bar into the ground and use it for grounding for the sub panel. I realize I’m in over my head for a correct permanent fix but replacing the use of the guy wire as neutral is better than what I have now, right?