I recently soldered (first time) a copper pipe to a water valve. There seems to be a pinhole leak causing water to squirt out. I tried to solder it again but the leak is in a tight area next to a cement wall.

I than tried silicon, puddy, and epoxy but they did not seem to help. (Possibly because there is water in the pipe, that cant be drained)

Any suggestions?

Jeffrey, April 2009

Forget about any epoxy or filler repair - unfortunately you'll have to drain down, unsolder to split your connection and re-do it. When the joint is split, polish up any faces to be resoldered with abrasive paper, flux the joint once more and try again. These always fail in the most inaccesible places, don't they?

John, April 2009