Need help with drain leak

[Spencer518]

I'm just finishing remodeling my bathroom. The new vanity counter has an undermount sink, while the old sink was a drop-in/topmount. Now the drain hole is lower in height than the old sink. As a result my trap arm is running uphill to the hole in the wall and the water level is high in the p trap. I know the standard solution would be to lower the drain hole in the wall, but that would be quite difficult for me as the pipe is going through 2 studs in the wall before meeting the vent. I took this photo 15 years ago when the house was being built. The wall is currently dry walled and tiled and it would be major work to move the pipe.

I went to Home Depot and got the PVC to make a new drain. My leak is coming from where the metal tail piece is going into the trap adapter. This connection has standing water in it. I've cranked the nut on top of the trap adapter down pretty hard with pliers, but a tiny amount of water is still leaking out. Not the best photo, but you can see some water on the top of the plastic nut. How can a create a permanent water tight seal here? I don't care if it means that the connection can't be undone. At this point I just want this thing to stop leaking. Is there some type of sealant or epoxy that I could apply. Thanks for any advice. Spencer

 

[Reach4]

I see water at location 1. Could location 2 and 3 be water also?

That is quite the casting. I think I see Teflon tape at 1. Do you have a very short tailpiece that is threaded into the casting?

 

[Sponsor]

 

[Spencer518]

The tailpiece goes about all the way down to the bend in the elbow. I used teflon paste on the screw threads at the top of the tailpiece. I don't believe it is leaking from there. There is no water at 2 or 3, just reflections off the chrome.

 

[Spencer518]

I'm thinking this stuff might do the trick?

 

[Gary Swart]

Open the wall and lower the drain like you already know is the right way. You can't make water run uphill. As far as the studs are concerned, that is not a load bearing wall, so you can notch as necessary. Yes, it will require some work. PVC thread should not be taped or puttied. Properly aligned and assembled, they won't leak.

 

[Reach4]

Do you have a link to whatever it is that includes that casting? I would like to read about the system.

I would not use that epoxy. It will not let you take things apart to clean or replace. Rectorseal #5 would be better. Gary Swart is implying that that leaking connection should not be below the P trap weir. I had wondered about that.

 

[Spencer518]

I guess I'm not good at explaining my leak. It's not leaking from any threaded area. It is leaking where the metal tail pipe is inserted into the trap adapter fitting. I've tightened the plastic nut as far as I dare, but the flange inside it isn't creating a water tight seal against the metal pipe. I want to put the putty on top of the nut where the metal pipe slips into it, where the water is sitting in my photo.

The casting is just part of the drain assembly that came with my kohler faucet. I shortened the tailpiece from 6 inches to 3 inches, so 2.5 inches of it is going into the PVC elbow.

 

[Reach4]

Is the tailpiece 1-3/8 OD or 1-1/2 OD? I wonder if you are missing a piece. Also, there seems to be some misalignment.

 

[Terry]

I guess I'm not good at explaining my leak. It's not leaking from any threaded area. It is leaking where the metal tail pipe is inserted into the trap adapter fitting. I've tightened the plastic nut as far as I dare, but the flange inside it isn't creating a water tight seal against the metal pipe. I want to put the putty on top of the nut where the metal pipe slips into it, where the water is sitting in my photo.

The casting is just part of the drain assembly that came with my kohler faucet. I shortened the tailpiece from 6 inches to 3 inches, so 2.5 inches of it is going into the PVC elbow.

The tail piece will be 1-1/4"
They make a 1-1/2" x 1-1/4" slip joint washer for that.
Though it may be that what you have is 1-1/4" already.

 

[Spencer518]

The tailpiece is 1-1/4. It is going into a 1-1/4 to 1-1/2 trap adapter. It's this item from Home Depot

 

[Gary Swart]

What part of "NO PUTTY" did you miss? Redo this right and things will work. You can just bend and twist to make it fit.

 

[Terry]

The tailpiece is 1-1/4. It is going into a 1-1/4 to 1-1/2 trap adapter. It's this item from Home Depot
View attachment 29442

That should work.
Are you sure the water isn't coming from farther up?
I often use putty on the threads up where the large rubber washer meets the bowl. Sometimes water will find it's way past that on the threads.

 

[Spencer518]

I'll take another look when I get home tonight.

 

[FullySprinklered]

Two things to check on: when you're tightening the nut on the trap adapter, you are turning it a direction that would unscrew the threaded metal tailpiece. Also, that tailpiece nut looks like the kind with the built-on ferrule (washer). Try the other kind; separate nut and ferrule.

 

[Spencer518]

That should work.
Are you sure the water isn't coming from farther up?
I often use putty on the threads up where the large rubber washer meets the bowl. Sometimes water will find it's way past that on the threads.

Terry - You are a genius. I ran the water last night for about 10 minutes and sure enough water started to come from between the big chrome nut that supports the rubber washer and the pipe. I loosened it up and put plumbers putty on the threads. It seems to be working fine now. Sounds like Kohler needs to update their installation instructions....

 

[Terry]

Terry - You are a genius. I ran the water last night for about 10 minutes and sure enough water started to come from between the big chrome nut that supports the rubber washer and the pipe. I loosened it up and put plumbers putty on the threads. It seems to be working fine now. Sounds like Kohler needs to update their installation instructions....

Thanks.
As plumbers this is how we install them It's not in any of the instructions. Nor do I expect it to ever be.
I get in trouble from other plumbers for telling this "trade secret".
It's why they have "trades" I guess. Some things are learned the hard way, or by working with someone that knows.