Why won't this connection stop leaking?

[bha]

Hi all

I have recently installed an automatic shutoff on my home water supply. I have all of the connections soldered and threaded properly, but one of them won't stop leaking.

Look at the ball valve with the red handle. Coming out above it is a male threaded fitting that is then soldered to the pipe above it.



I can't get the connection between the ball valve and the male fitting to stop leaking. I cranked it really tight and am afraid to tighten it more for fear of stripping or breaking it. This is with two 12" wrenches on it so it's pretty tight.

I had thread lubricant on it (Megaloc?) and removed it and things got slightly better. A very tiny pinhole type stream of water went away and now the threads are just dripping slightly. One drip about every few seconds.

Replaced the ball valve, no change. Thought the threads were stripped or damaged even though it was brand new.

Replaced the male fitting (desoldered and then re-soldered a new one on the pipe) and no change.

All of this is 3/4 copper

Wondering if maybe I have the wrong male fitting? Is there a different type and I have the wrong one? (compression, MPT, etc.)

This is the exact male fitting I purchased:
https://www.homedepot.ca/product/aq...er-to-male/1000116933?searchterm=773638758161

Since the copper nipple coming out of the bottom of the ball valve doesn't leak, I'm considering just putting the same kind of nipple in the top, and installing a female fitting on the pipe and connecting to that. Basically the female version of the male fitting I've shown above, plus a nipple between that and the ball valve.

BTW when I put a 3/4" plug into the top of the ball valve and run everything with full water pressure, it works fine. It's definitely the male fitting that is the problem for some reason!

I guess another option is to go from the nipple (going into the bottom of the ball valve) to a female adapter, then solder in a ball valve on the pipe (so no nipples going into or out of the ball valve.. just a pipe with a ball valve soldered into the middle of it. Same # of connections but I can avoid this pesky leaky connection

Any thoughts?

 

[Ryan Symons]

Tape then dope.

 

[Sponsor]

 

[Jeff H Young]

sometimes threads just arent machined quite right how much tape did you put? clean treads with wire brush then put 6 wraps

 

[bha]

Didn’t use any tape at all. I tried using “sealant” but then figured it might be causing the problem. So I wiped it all off (there is still a small amount between the threads that I couldn’t clean out) and tried without any sealant. Leaked both ways

Here is the sealant I used:
https://www.homedepot.ca/product/oatey-1-1oz-megaloc-pjc/1000723575?rec=true

So I should clean up the pipe threads (remove all the sealant from both surfaces) and use 6 wraps of teflon tape instead?

 

[Ryan Symons]

Use both. Wrap tape first then dope on top.

 

[bha]

Aha! Ok so seems that tape could be the missing link.

I'll try 6 wraps of tape (correct direction) with dope on top.. will try first thing in the AM and report back on results.

Thanks!!!

 

[DIYorBust]

I believe your problem is that the joint is not tight enough. Break the union, and tighten that fitting down. Use a 14 inch pipe wrench and hold the valve back with another wrench. You do not need to go crazy. Try another half turn, or a full turn depending on how it feels. On an older pipe I did recently, I had to go all the way to the end of the thread to stop the leaking. I was out of thread, so I was very happy it didn't leak after that.

It's true the threads are sometimes poorly machined, but if he replaced both parts with new and got the same issue, it seems the problem is more likely with installation process. Usually upping the tape and dope is for older threads or when there is a bigger job and leaks would mean disassembly. For a brand new valve with easy access and union nearby, it seems like a good joint should be doable. Personally I use just tape in situations like this. A better quality tape is probably worth it, or possible one of the oatey special colored tapes. Dope is a bit messier and less forgiving if you get it somewhere it shouldn't be, even megaloc. But even with cheap tape that came with a showerhead, you should be able to make this work. Good luck!

 

[Plumber69]

use both.

 

[Sam M]

I had issues with an expansion tank leaking at the threads. New tank, new fitting. Used tape and a light layer of dope, no leaks.

 

[Reach4]

I think it is worthwhile to use better PTFE tape. The good stuff has more PTFE, and is thicker.

https://terrylove.com/forums/index.php?threads/how-much-ptfe-tape-should-i-use.65941/#post-489815 has some thoughts on PTFE tape technique and selection.

https://terrylove.com/forums/index.php?threads/yellow-gas-ptfe-tape-on-potable-water-line.81475/ is a thread that discusses using yellow tape on potable water.

 

[Jeff H Young]

the copper male adapter that he replaced was probebly the same batch and just a bit off so you replace it with an Identical one . I notice with threaded fittings youll notice that all the 90s screw on a certain amout by hand and then the tees or couplings will be a thread or so differant. Ive also noticed more trouble with Copper , than brass, black or gal fittings .
Some guys dont use tape at all some use tape only and some use both they argue you dont need one the other or both , that its sloppy work . When everything is perfect its almost impossible to get a leak, but nothing is perfect. Ive done miles of screwed pipe (literaly). You gotta keep your eyes open inspect Install a big system when you get done gotta test it out . No matter how good you are , luck plays a part . Any way I vary my tape with how the fittings screw together. Wrap the tape clockwise and use dope as well. Im not tightening it but possible you need a bit more tight

 

[bha]

SOLVED!

First of all THANKS everyone for your help!

Disconnected the male fitting, cleaned it well, applied 6 turns of pink Oatey tape in a clockwise direction, then a dab of Megaloc. That pink tape is very thick compared to the usual, but wow is it ever great! Wasn't sure 6 turns of pink tape would even get the fitting started, but it did.

Also applied tape and sealant to the union nut just for good measure

Turned on the water and both fittings are BONE DRY. Not a drop, no weeping, nothing. Has been on for an hour (with all fixtures shut off so there is maximum water pressure in the system) and no signs anywhere of a leak. I would have collected around 1/2 gallon of water during that time yesterday from the dripping.. and not one drop today!

Wow, had no idea tape and dope would make that much of a difference. I'll be using it on all connections going forward!

 

[Reach4]

Glad the NPT thread leak has stopped.

A piece of that pink stuff will sink in water once you get the bubbles off. The cheap tape will never sink in water, because the fillers have a lower specific gravity.

Also applied tape and sealant to the union nut just for good measure

That would not be something you would usually want to do. A little dope as a lube, or silicone grease as lube, can be useful. But next time I would not use the tape on the union. I would not remove the tape that is already there, however.

 

[Jeff H Young]

I think it is worthwhile to use better PTFE tape. The good stuff has more PTFE, and is thicker.

https://terrylove.com/forums/index.php?threads/how-much-ptfe-tape-should-i-use.65941/#post-489815 has some thoughts on PTFE tape technique and selection.

https://terrylove.com/forums/index.php?threads/yellow-gas-ptfe-tape-on-potable-water-line.81475/ is a thread that discusses using yellow tape on potable water.

Thanks reach4! Interesting about the yellow tape. Its been controversial subject for me. Just wanted to say Inspectors can cause grief. Not using an aprooved dope or tape for whatever it is gas or potable water can make you tear it all out. Dosent matter how safe the product is or what its made out of its the Legality of it. Ive installed so much gas line with white tape on big jobs , I wont argue I will bring it up once tell them I need aprooved tape and If they say go it aint my problem

 

[Jeff H Young]

6 wraps mighta been over kill on the thick tape but you get a feel for it

 

[Reach4]

Ive installed so much gas line with white tape on big jobs ,

There is good white PTFE tape. I think the MIL-T-27730A spec tape was usually white. AFAIK, everything was white for a long time. But at this time the cheap stuff is white, as far as I have seen. That could change. Maybe the inferior stuff will start getting a color.

Pure PTFE has a specific gravity over 2.

https://en.wikipedia.org/wiki/Thread_seal_tape

 

[bha]

6 wraps mighta been over kill on the thick tape but you get a feel for it

Probably was, but I assure you this was the *final* time I was ever going to be putting this fitting together so overkill is fine with me

 

[Chucky_ott]

I know you didn't ask but did you use flux on your soldered joints? From the pictures, they look less than ideal, even if they don't leak.

 

[bha]

I know you didn't ask but did you use flux on your soldered joints? From the pictures, they look less than ideal, even if they don't leak.

Yes used flux and soldered properly. They’re just a little messy.

I didn’t wipe them with a wet rag etc. Just soldered them up good & tight & messy

 

[Plumber69]

I know you didn't ask but did you use flux on your soldered joints? From the pictures, they look less than ideal, even if they don't leak.

Was going say same thing. Doesn't look like it penetrated that much