I'm talking about those slip on tub sprout that forces water to go to the shower head if you pull the handle at the tip. It is in a bathroom that I haven't used since I bought the house years ago (guest room). I'm expecting a guest this weekend so I test it out and found that it is leaking at the front. I've replaced it before in my other bathroom so I decided to replace this one myself. I use a hex key to loosen it and slip on a new one, then tighten it and test. Water stream out of the rear as well as the front. The instruction on the packaging said that the stub out nipple from wall surface must be between 2" to 3" long, but mine is only 1" from the wall. It also said not to over tighten the hex key when install, or may risk permanent damage to the stub out nipple. I felt it while sanding off deposits and sure enough, it was over tightened in the past and bend inward where the hex key meet the tube/nipple. I see where the O ring mark land on the nipple and found old Teflon tape when I took the old one out. I tried new Teflon tape but it is still leaking in the back. To be safe I use plumbing putty to seal the wall just in case water leaks into the wall, but I know that it is not going to be a perfect seal and I need to find a way to fix it once and for all. Any suggestion? Do I need to cut and weld a new piece of copper just for this? Should I caulk it with silicon caulk? automotive grade gasket maker? My main concern is if I use caulk or gasket maker it would be very difficult to replace it next time.