Bert Byfield wrote:
....
But my primary leak right now is where a water pipe has been touching
the conduit for the main house power for fifty years or so, and the
contact has caused a pinhole leak, of 5 or 6 gallons a day. I'm
looking at inserting a "universal pipe repair clamp" between the pipe
and the conduit, before I think about replacing sections of pipe.

All you need is a slip over coupling (one w/o the ridge in the middle)
expressly for the purpose.

Cut the pipe at the location of the pinhole, clean the ends (remember to
also ream the inside of the cut to get rid of burs), then slip the
fitting over, flux and solder. Done.

Then, as somebody else noted, fix the contact point so the two don't
touch in some fashion and it'll probably outlast you.

I'd not worry about the rest until actually had a demonstrable problem.
Like the above, unless you have something very corrosive in the water
or other problems, likely it will no longer be your problem when it
actually requires replacement.

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