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(Solved) Faucet plumbing question on finding compression plug

A&P mechanic

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324
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FL
Hi GJ,

  • Could you provide a link and the proper name for a compression plug to allow me to plug this 3/8 inch flexible water line temporarily please?

Big picture:
The on/off was leaking under the sink, so I removed the valve and capped it temporarily with a shark bite plug.
The new hollow nut for the shut off valve did not slide on the copper pipe since the pipe is distorted.
I pulled the copper ferrule off, the nut was likely tightened to much originally.
I will cut the bad piece of copper ½ inch pipe off and solder a new pipe extension on then install new compression shut off valve on this weekend.
I would like to temporarily plug the flexible line until I have time on Saturday in a few days to fix it correctly.
I went to Lowes tonight but did not see any compression plugs.
I did see compression caps but I need a plug.
I am not a plumber and am learning as I go.

Thank you in advance!
 

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OP
A

A&P mechanic

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I don't think I've seen compression plugs...

Why do you need to plug the flex line?
To use the faucet.
There is a hot and cold shut off valve.
I plugged one valve, however, at the top of the sink, there is a small mixing flexible line that pours water out when I turn the 2nd water handle on.

You might need to use a short piece of copper with a compression fitting to the valve, and a compression cap. About all I can come up with!
That's a unique idea but I am wondering if anyone else chimes in with an off the shelf plug or another solution. Thank you!

I removed the flexible line and then capped above it with a compression plug along with teflon tape but it still drips.
I feel like the compression cap needs an o-ring or maybe the threads are different like NPT vs compression threads.

I think the best bet might be to plug the flexible line
 

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paulsomlo

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I think I see what you're trying to do - you want to still be able to use the faucet with just the cold water line hooked up to it. In theory, if you've got the other faucet handle shut off, I wouldn't think you'd get any water crossing over to the unused side, unless you've got a worn faucet washer or cartridge. Even so, I would think the dripping to be minimal enough that a bucket under the sink would take care of it temporarily.
 

paulsomlo

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You might be able to use the new valve as a plug - screw it on and leave it closed, just hanging from the flexible line. I know the ferrules are supposed to be single use, but cheap enough to replace when you make everything permanent. Although, I'm surprised to see a brass ferrule in conjunction with the 3/8" connection to the valve - what I'm used to seeing is a rubber cone integral to the flex line.
 
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A

A&P mechanic

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I think I see what you're trying to do - you want to still be able to use the faucet with just the cold water line hooked up to it. In theory, if you've got the other faucet handle shut off, I wouldn't think you'd get any water crossing over to the unused side, unless you've got a worn faucet washer or cartridge. Even so, I would think the dripping to be minimal enough that a bucket under the sink would take care of it temporarily.
Correct. I plan to use just one side/ the cold water temporarily for a few days.

I just put a bucket underneath instead of the tubber ware container.
I replaced both sink cartridges Saturday.
The on/off underneath started dripping when I shut the water off to change the sink cartridges, so I started to work on replacing the shut off valve this afternoon but stopped and will continue again this upcoming weekend.

Appreciate your input!
I am curious if anyone else comes up some type of plug I can order online, preferably from a big box store then I can use the plug this week and keep it for the future if I ever run into this issue again.
I have several of them but you need 1 now.
a pc of 3/8 OD tube with a ferrule on one end, crimp & solder the other end is a quick way to do it.
or 3/8 " round rubber ball under the compression nut works good too .

pic of a 3/8 compression plug https://www.masterplumber.ca/product/compression-fitting-plug-3-8/
1764637840628.png
Great input with picture!
This looks like a cap, I am wondering if there is one that looks like a plug with threads to push into the flexible hose?
I like the rubber ball idea, that is unique.

You might be able to use the new valve as a plug - screw it on and leave it closed, just hanging from the flexible line. I know the ferrules are supposed to be single use, but cheap enough to replace when you make everything permanent. Although, I'm surprised to see a brass ferrule in conjunction with the 3/8" connection to the valve - what I'm used to seeing is a rubber cone integral to the flex line.
Dang, that is good idea too!
If the old shut off valve stayed close, then all the water would stay in the line until I unplugged the old shut off valve next weekend.
 

KenC

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I'm way late but, 3/8 compression to 1/2"mpt adapter with a 1/2"fpt cap.
 

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OP
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Hi GJ,

Everything is fixed now with no leaks.
I actually did not need to solder.

The new compression nut did not go on the pipe but the old compression nut did slide on the ½ inch copper pipe.
Therefore, I removed and replaced the copper ferrule then reused the old compression nut.

I also had the thicker type L ½ inch copper pipe.
I did an internet search and learned both type L and M have the same outer diameter and that the copper pipe is likely deformed and that is why the new compression nut did not slide on.
Oddly enough, the new compression nut did not slide on the new ½ type L copper pipe I bought either. It was very close but did not fit.

I felt it required a lot force to get the compression nut seated to prevent any leaks. I did use pipe dope. I originally used my hydraulic wrenches then switched to a regular combination wrench for more leverage. I watch a youtube video prior that said just keep tightening until the water no longer leaks out, that made sense to me. I used the construction jack to hold one wrench steady at the correct height while I tightened the nut with the other wrench.

I am buying a few sizes of compression to IPT adapters with IPT caps to keep in my plumbing box. KenC hit the nail on the head!
I learned a lot of about compression threads vs NPT threads vs IPT threads this past week.

For awareness, OD compression to NPT brass adapters are difficult to find in that HD and Lowes do not sell this, so IPS adapters it is then for the future.

Everything is good now and I appreciate all the replies!
 

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