Leaking sillcock at threads...

[gregk24]

I posted yesterday that I replaced a water spigot at our house (front yard). Well this morning I ended up replacing the one in the back yard too. Well, it seems as if there is a slow slow drip, and it appears to be coming from where the faucet screws onto the threaded pipe protruding out of the wall. I did use teflon tape during install.

So what should I do? Maybe take off faucet, wire brush threads, reapply teflon tape and cross fingers?

 

[Nick1994]

Sometimes it takes 2 tries, and maybe a little more snug. Might not be able to make it perfectly straight up and down, might need to be a little crooked.

 

[gregk24]

Originally Posted by Nick1994
Sometimes it takes 2 tries, and maybe a little more snug. Might not be able to make it perfectly straight up and down, might need to be a little crooked.


I went out there tonight and tightened it up a bit more (it is VERY snug) and I am scared to break this old pipe! But no luck, still a very slow leak. Im taking maybe a drop every 5 minutes, but still it shouldn't leak at all.

 

[maxdustington]

Try a few more laminations, if that does not work try pipe dope or thread sealant.

 

[billt460]

Use several layers of tape and pipe dope.

 

[dbias]

Is the "old pipe" galvanized? If it is it may be rusting through the thread area that got disturbed during the change out. In that case you need to replace that pipe at least back to the next union or elbow.
If it's not galvanized is the new spigot threaded straight into the old pipe or are you using a flexible hose to connect the two? If so those flexible lines should not be over tightened as it will cut down the rubber bushings inside the connector.

Reread edit.... my bad initially I thought you were replacing a freeze proof spigot and the leak would be under the house.

 

[doitmyself]

Follow bilt460's advice. I see the pros do it often. I've had drip problems even on new galvanized pipe and fittings.

 

[Papa Bear]

I'll come down in late November and fix it for you ... should be done about April.

 

[Delta]

As said before tape and pipe compound on old galvanized. 4-5 layers of tape and apply a heavy coat of compound. I recently have been using Rectorseal and have had success with it. I usually use it without tape, but that's on brass air fittings an new galvanized that was "factory" cut. Sometimes the old was cut on site in less than optimal conditions.

 

[WyrTwister]

Originally Posted by maxdustington
Try a few more laminations, if that does not work try pipe dope or thread sealant.


I would try pipe dope or maybe Permatex non hardening automotive sealant .

But before I did that , I would source a spare faucet , in case the one that is there has a crack that only opens up when the faucet is screwed on tight .

Are you able to get on the pipe with a wrench ?

 

[gregk24]

Ok guys, I ended up getting a wire brush, pipe dope, and a new sillcock faucet. I took off the one that I installed yesterday and wire brushed down the threads on the galvanized water supply line. There was lots of gunk on the threads that have been exposed to the elements for the past who knows how long, and most of that did NOT come off, even with WD-40 and the wire brush. It did however clean up the threads that were exposed by removing the faucet. I then thoroughly applied the pipe dope all over the male threads and even further up the pipe (I figured it would have some rust proofing benefits) maybe not, but I didn't think it would hurt.

Once the pipe was coated in pipe dope I threaded on the new sillcock, it certainly went on more smoothly than it did yesterday. I snugged it up with a wrench and turned the water supply back on, so far no drip!

 

[gregk24]

I checked again for leaks both this morning and just now. It appears to still be producing a drop of water every 10 minutes or so. The leak is coming from the threaded area. I suppose I will just have to live with it at this point. Either that or tear into the wall to re-plumb a new pipe (not interested).

 

[doitmyself]

You still haven't tried the recommendation to use BOTH tape and dope. Put about three good overlapping layers of teflon tape on, wrapped tight and in the correct direction. I then take my dull, not sharp, fingernail and gently run it in each taped pipe thread groove to seat it in the thread just a bit. You don't want to cut through the tape with a sharp fingernail. Then apply the dope generously. Too many wraps of tape and it will just push off as the fixture is screwed on.

Also, run that hose bib onto the steel threads dry a few times before final assembly to smooth any possible burrs off (the Chinese bib). Don't torque it down, just on and off by hand a few times.

I witnessed the pros doing this on NEW galvanized fittings and they were blaming poor Chinese quality control for having to do this on problematic joints. You have nothing to lose trying it.

 

[gregk24]

Originally Posted by doitmyself
You still haven't tried the recommendation to use BOTH tape and dope. Put about three good overlapping layers of teflon tape on, wrapped tight and in the correct direction. I then take my dull, not sharp, fingernail and gently run it in each taped pipe thread groove to seat it in the thread just a bit. You don't want to cut through the tape with a sharp fingernail. Then apply the dope generously. Too many wraps of tape and it will just push off as the fixture is screwed on.

Also, run that hose bib onto the steel threads dry a few times before final assembly to smooth any possible burrs off (the Chinese bib). Don't torque it down, just on and off by hand a few times.

I witnessed the pros doing this on NEW galvanized fittings and they were blaming poor Chinese quality control for having to do this on problematic joints. You have nothing to lose trying it.


I tried again this afternoon. Took off the valve, wire brushed the threads of the water supply pipe, then applied the plumbers tape and coated with pipe dope. Still leaks.

 

[doitmyself]

Ask Papa Bear if he has ever used lamp wick thread sealant and a "more substantial" thread sealer like Hercules Blue Block or Permatex #2 to repair damaged threads.

 

[gregk24]

Ok guys, I went out and purchased another new sillcock valve this evening and attempted to stop this leak AGAIN for the fourth time. So far, it seems there is no leak! I took the old valve off and poured straight up CLR on the water supply line threads, followed by a wire brushing. I did this maybe 5 or 6 rounds before rinsing and drying the pipe off. I then applied 2 separate strands of plumbers tape, each strand overlapping itself multiple times. As recommended by another member I "sealed" the threads by running a fingernail around them to adhere the plumbers tape better. I finished up by applying a moderate layer of pipe dope and then screwed on the new sillcock valve as far as I could by hand and turned it a final time with a pipe wrench. It did go on further than before, probably due to cleaning the threads more thoroughly.

Glad it seems to be holding so far. I will check again later tonight, because the first two attempts appeared not to leak at first only to check back later to find a slow slow drip!