I am not a plumber. This fact will become obvious shortly. I replaced a bathroom sink faucet last weekend and I have a couple leaks that I need advice on fixing. When I replaced the faucet, I also replaced the shut off valves since the old ones were junk. My leaks are a slow drip from where the shutoff valve threads onto the C PVC threaded male fitting. I have since went back and used both pipe dope in conjunction with the Teflon tape but still have a slow drip. After looking at it a third time, I think the PVC threads don't look good. I'm sure I need to replace the CPVC male nipples, but as you can see, I don't have a lot of existing length of pipe to cut to get them off. I'm wondering if I cut the 1/2" pipe (which is only 1/4" long) and then cement a coupling onto it with a short piece of 1/2" pipe and then the threaded male? I'm concerned the existing 1/4" long pipe is just too short to make a good connection? What do I need to do, without cutting up the Sheetrock if at all possible?
It didnt have the clap before right? If it didnt I would first rule out the fact that you got a SOV with bad threads. They arent that costly and having extra plumbing stuff around is always a good thing. They do make reamers for taking out those short lengths you have in the existing couplers but are around 50 bucks for a 1/2 inch line. Unless a rental supply has them or a buddy of yours happens to have some. Is it the line on the left that is dripping? It almost looks to me as if it is cross threaded and may not be tightened down enough also. To me, worse case scenario, cutting the rock under a vanity and fixing it from inside the wall out aint that big of a deal. Fix pipe, patch rock as best you can, wife or girl friend stuffs so much stuff under the sink you will never see it again.
Didn't leak before, and yes I think I cross threaded the one on the left. PVC threads are shot I think, since I tightened the heck out of it to stop the leak. Picture also showed me after the fact that the left one is cross threaded.., And I tried to make sure I didn't do that to begin with. Both are leaking, might be able to ratchet the right one tight, but I already have the left screwed up for sure so I thought I would do the same fix on both just to be sure. I like the idea of cementing a threaded adapter on both, but haven't found with a Google search a 3/4 female to male threaded adapter . If they don't make such an animal available at Home Depot, maybe a female to female fitting and then a male threaded nipple? Still trying to avoid cutting the drywall, even though that would be a solution for sure. All good advice guys..,,
I would think a female glued to the male would hold, then you can attach whatever you need. If not, you aren't out much...
Remove the stops. Apply pipe dope. very light coating. then teflon tape. three to four wraps. clockwise. then pipe dope again. very light. get it started straight and it should turn 3-5 turns by hand before getting tight. another turn or two with a wrench. we call it "dope tape dope" if that doesn't do it, I'd cut the male adapter off and glue on another one on the short stub. Let it dry for an hour or two. if that doesn't do it...cut the drywall...
You might be able to find a 1/2" fitting saver and cut the tubing at the reducer and put a new piece of 1/2" tubing in
The stop means the shut off valves I assume? I did the pipe dope and then tape, but didn't do the dope over the tape. This is my first rodeo using steel valves to the CPVC threads, and other than me cross threading on the third attempt on the left one only, I was surprised that when it got tight it didn't want to tighten much. Not like threads on brass or steel, that you can go many turns before they get tight. My first experience with these steel valves threaded to CPVC, once it got tight you couldn't tighten a whole heck of a lot more. And once it got tight which was very quick, it wouldn't go much more before I thought I would break the pipe. I use to install gas pipe in my early years for all kinds of residential and commercial applications and you could tighten until no leaks, I felt that with this situation, once it got tight that was it, very little tightening once it was tight, not considering the cross thread issue on the one valve. Once tight I was lucky to get one full turn. With that said, I was concerned I would have the valve going straight up since it seamed to tighten and that was it. With that said, I appreciate your advice. I might give it another try, but worry I screwed the threads on the left already.
An easy fix would be Shark Bite angle stops. But i think you'd need almost an inch of tubing to push it on. SharkBite 23036-0000 Angle Stop 1/2" x 3/8" Compression SharkBitePlumbing.com
I'd pull it apart and try to thread it back on straight with the dope tape dope as Tim said. If that doesn't hold then I'd glue a threaded coupling on there and then thread a "close" nipple in it, then your valve goes back on. Be careful you don't over tighten the threaded coupling on either side...they are easy to crack...I hate using threaded plastic fittings (female) just for this reason...if they don't crack when you put them together sometimes they crack all on their own later on. They do make some that have a metal band to re-enforce so they don't break as easy...hard to find though. In the past I have done DIY re-enforce by putting a hose clamp over each end
I have run into female threads not being cut deep enough on fittings. I would try 2 new valves and see how far they thread on. Then I would consider gluing females onto the males, I would probably lean towards cutting the 3/4 flush with the wall and glue on new 3/4 to 1/2 reducers with a 1/2 stub a couple inches long and a glue on shutoff valve eliminating the threads completely.
if you find a fitting saver be really careful, CPVC gets brittle and if it grabs you will be removing a lot of drywall to repair it
Update.... I pulled off the ball valves and cleaned the blue dope and Teflon tape off the CPVC threads. Found out that blue dope does not want to come off easily! Then cemented the threaded CPVC female adapters to the males. Decided to not cross thread one this time around. Then on my workbench, screwed on my shut offs to female threaded CPVC adapters using the suggested dope, tape, dope method and then cemented a 1.5" nipple into the adapter. Final step was cementing the other end of the nipple into the other adapter under the sink. Valves point straight up. Let dry 3 hours. And..... No leaks!! Sorry no pics this time. Thanks for everyone's suggestions, couldn't have done it without you.
never had a plumbing repair yet that didn't require 3 trips to the store- never seem to have that problem with hydraulics or electrical issues. Go figure. case in point last time out extending gas line, black pipe cut and threaded to lengths needed at store get back- noway in H were the fittings threading on- don't know what they did at store but I ended up rethreading the 3 sections I got by hand ( I have a full set of dies & taps).
