New Bathroom Sink Draining Issue

[esjr]

Hello,
My issue is I have recently installed a new bathroom faucet and matching drain. When I turn on the faucet the water eventually backs up the drain and fills the basin. The sink is equipped with an overflow drain. When I installed the new drain I cut the side hole (on the new drain downpipe) to be bigger to allow it to line up with the existing overflow hole. Did I somehow get air trapped inside keeping it from draining? Interestingly, I installed just the old drain back into the basin and it still backs up. I also went on top of the roof to look into the vent stack and didn't see any obstruction. It does not have (nor ever had) a AAV installed. Also the sink is NOT a vessel sink. Below the sink is a typical down pipe to a P-trap then into the wall. Standard it seems.
Thank you for all the wisdom shared here inside these forums. Your expertise is appreciated tremendously!

 

[WorthFlorida]

Making the side hole larger was not necessary. The overflow built into the sink basin surrounds the drain pipe so overflow water can flow from anywhere. Notice below the white channel goes around the drain.

Have you tried the drain without the stopper? Did you remove the trap completely and clean it? With the trap arm removed eyeball the drain pipe with a flashlight. For bathroom sinks clumps of hair is usually the culprit.

 

[Sponsor]

 

[Terry]

It's likely needing to be snaked. A bathroom sink can have toothpaste, hair and soap in the waste line.

The other thing to check is how far the p-trap goes toward the wall. I always cut them off flush with the wall so that the end piece doesn't block the 90 or santee in the wall.

 

[esjr]

Making the side hole larger was not necessary. The overflow built into the sink basin surrounds the drain pipe so overflow water can flow from anywhere. Notice below the white channel goes around the drain.

Have you tried the drain without the stopper? Did you remove the trap completely and clean it? With the trap arm removed eyeball the drain pipe with a flashlight. For bathroom sinks clumps of hair is usually the culprit.

Thanks for your responses. The sinks overflow drain ends with a hole not a channel described in your image. Similar to how it begins at the top of the basin. I have removed the pipe completely down to the p-trap and cleaned it. I ran nearly 25 ft of snake into the pipe and there was nothing that would cause a clog. I have tried the drain w/o the stopper and it backs up. Oddly, this sink was working fine before the new faucet install. Did I somehow trap air inside? :-\\

 

[Reach4]

To test for the air thing, shove a soda straw down the drain, and let air below come up through that straw. If that increases flow, then your drain may not be connecting sufficiently with the overflow area. The overflow holes can not only let water go down, they can let air escape.

 

[esjr]

Hello Reach4,
I did clear out the overflow tube. It wasn't bad at all. Nothing obstructing it. However, I would like to test your theory. I'm not sure i understand the process.

 

[Reach4]

Can you lift out the stopper, and if you do, is the flow no-problem?

Can you have the stopper open, and slip a small tube, such as a soda straw, through the crack, and down to the pop-up area?

The problem is not a vent thing that outside of the sink area before the trap.

 

[esjr]

Turning the water on lightly, I remove the stopper, look down the pipe and see the water traveling back up. The more I open the valve the faster it backs up. Just so I try this correctly, was this how you suggested I insert the straw into the drain? Thank you!

 

[esjr]

Yes so I tried this and it didn't change. The water still continues to climb back up the drain pipe. :-\

 

[Reach4]

That is how I pictured the straw.

Interesting. I would take the slip p-trap off, and put a bucket under the tailpiece. See how the flow is then.

OK, that is probably going to flow really well. But what if the blockage is in or beyond the p-trap?

 

[esjr]

That is how I pictured the straw.

Interesting. I would take the slip p-trap off, and put a bucket under the tailpiece. See how the flow is then.

OK, that is probably going to flow really well. But what if the blockage is in or beyond the p-trap?

Hello,
I have ran a snake directly into the wall w/o the p-trap installed. The total for the snake is 25ft.

 

[esjr]

Here are some pictures.
Thank you for your time!

 

[Reach4]

Is that J-B Weld, or similar epoxy in your PXL_20210429_012538934.jpg photo? Has the bore been reduced?

 

[MACPLUMB]

Your drain needs to be "POWER" snaked it might take 30' or more to clear the blockage !

 

[esjr]

Is that J-B Weld, or similar epoxy in your PXL_20210429_012538934.jpg photo? Has the bore been reduced?

Hello,
That is just water. I used plumbers putty to seal around the flange. I'm not sure if the bore is reduced. What is the bore?

 

[Reach4]

That is just water. I used plumbers putty to seal around the flange.

Good.

What is the bore?

The water path inside of the drain assembly.

How far down do you think your straw reached? Just below the drain actuation lever?

Does the water go down easily when the stopper is out? If yes, then it is not a drain problem.

 

[Jeff H Young]

so in 25 foot your lav doesn't join another drain ? unusual. maybe snake isn't going down it could be going up vent?

 

[Terry]

I replaced this tub drain yesterday and replaced the bathroom lav and faucet. All tied together.
When I tested the bathroom sink, water came up in the tub. The homeowner said, "Yes, it's been doing that when we drain the sink after brushing our teeth."
Looks like I will be sending my friend Walt in to do some snaking.

Pulled out an old three handle valve and replaced with the Moen Posi-Temp and a TL2368EP trim.

 

[Mr tee]

The drain is clogged.

 

[Tuttles Revenge]

We can see old Durham cast iron threaded fittings.. Very likely the drain is clogged and just as likely the snake is going up the vent when it hits that terribly constructed Durham san tee.