Need help understanding sink drain leak

[dperry9]

Hi everyone,

I live in a fairly old house (from the 40's) and the plumbing has presented problems off and on. the latest problem was I had a clogged P trap and I put Drano in it and then I slipped a coat hanger down in there to try to break up the clog a little. I didn't really use much force but I realized there was a leak soon after under the sink.

It's actually coming from the pipe where it enters the wall. I can't understand why this suddenly happened since, as I said, I wasn't putting really any serious force at all on the pipe when I used the coat hanger, and this is not a leak I've ever noticed before. It now seems to be getting worse. There's a collar covering where the pipe meets the wall so I can't see directly what's happening. These are all metal parts.

My questions are: why would something like this come about so suddenly when nothing major was done to any part of the pipe or trap?

And: is this something I can probably fix or do I need a plumber? I'm fine with basic plumbing repairs but I'll need to know what tools are required.

Thanks in advance,
Dave

 

[dperry9]

One other bit of info: the sink was backing up, but now it's not. The pipe just leaks at the wall when I run the faucet. So if the pipe is clogged, I can't understand why it's not just coming up into the sink.

 

[dperry9]

And one other thing. The bottom of the P trap is corroded and did develop a small hole when I used the coat hanger. I plan to replace it but for now I put a pitcher under it and I've watched and the drip into the pitcher is small--almost all the water leak is coming from the wall area.

Could the hole in the P trap somehow be changing the pressure in the pipe or something that could be leading to the leak at the wall?

 

[johnjh2o]

Never use drain cleaners. They don't work and are not very good for the plumbing. At the least the trap needs to be replaced. My guess is the line is still plugged. The reason it's not backing up is because it leaks out of the failed tap. From the questions you're asking I would advise you to call a qualified plumber.

 

[dperry9]

Thanks for the reply. You wrote "leaking from the failed tap". Did you mean to say "from the failed trap"?

It's not leaking from the trap, it's leaking behind where the trap joins the stub, and it's draining down the wall. I see no water coming from the trap. There's no leak at the connection between the stub and the trap that I can see, the water is just coming out from under the collar which sits against the wall. How can that be because of a trap failing?

 

[johnjh2o]

Sorry I did mean trap. The section that goes back to the wall and under the collar is also part of the trap.

 

[dperry9]

Sorry I did mean trap. The section that goes back to the wall and under the collar is also part of the trap.

Ok, so are you saying that broke somehow, at the wall (not the P section)?

I don't understand that at all. I did almost nothing to this pipe. I put a coat hanger down there and gave it a few little thrusts, not at all very forceful. This is the first time I have ever put a drain clearing product down there.

The P trap broke through slightly because it was already corroded (which I didn't realize). But I see no corrosion at all near the wall.

I need to have some idea what kind of a repair this is. I'm not in a financial position to have someone have to go in and open up my wall at this point. But I'm not incompetent with repair to the point that I can't replace a P trap, so if that will fix this, I'm going to do it myself. The truth is, right now I don't have much other choice.

 

[havasu]

Many are in your same position. All I could recommend is to post some various pictures here (give me a PM if you need help on pic posting) and let the experts walk you through the process.

 

[dperry9]

I guess what I'm asking is this: why is there water coming from the wall area when I didn't touch the pipe at all back there?

In order for water to come out, there must be an opening, right? But what caused a breech in the pipe back there? There is no way I got all the way up through the P trap and back to the wall with my little coat hanger. I'm sure it bottomed out at the bottom of the P section. But that's not where it's mostly leaking from, it's leaking way beyond there under the collar.

That's why I was shocked when I saw that leak. It doesn't make any sense---it should just be draining out the bottom of the P section but it isn't.

 

[dperry9]

Many are in your same position. All I could recommend is to post some various pictures here (give me a PM if you need help on pic posting) and let the experts walk you through the process.

Ok, I appreciate the support. It's just an average sink setup, though.

If you look at this video, my situation is that the bottom of the P section is corroded and has a small hole, but all the water is draining from that collar that butts up against the wall, very little is coming out of the bottom of the P section. The sink is not backing up.

[ame]http://www.youtube.com/watch?v=qPrYfMAdRio[/ame]

 

[dperry9]

Do you think there might be a loose connection behind that collar? I thought the pipe just went straight back into the wall there without a joint but if there is a joint behind that collar, maybe it started leaking?

That still leaves it as a mystery as to why that would suddenly start up when I tried to clean the P section out, since they are pretty far apart from one another, but stranger things have happened. I guess if the clog somehow worked it's way all the way to the back section of the trap, where it meets the wall, it might be forcing water out of a loose joint right there.

I'll try to get that collar pulled away from the wall and see what's back there tomorrow.

 

[havasu]

You can guess all day but to be honest, until you pull off the escutcheon and do some investigation, it could be numerous things wrong. Hopefully the bottom of the chrome pipe which goes into the wall has corroded from the drain cleaners. With any luck it will unscrew and it can be replaced.

 

[johnjh2o]

There is a good chance that your Draino destroyed a section of pipe that was about to fail. Like I said before the line is still plugged and it's going to need to be snaked with the proper equipment. So to put you back in working order is going to require the trap replaced back to the wall at least and the line snaked. If you can get the use of a snake a feel you are able to use it and change the trap then have at it. We're here if you should get into trouble.

 

[dperry9]

Wow, that sounds awful. Damn. I'm pretty much broke right now too.. Could hardly have come at a worse time.

I'm amazed that one shot of Drano would do this, but obviously something bad is going on back there. Maybe when I pull the P trap off I'll be able to clear whatever is clogging at the wall without it being a huge production and then I'll go from there.

Can I replace the worn out parts with PVC or do all the replacements need to be metal?

 

[dperry9]

I know you guys wanted a picture of my leak (my cell phone camera is crap, though) but this image shows a nearly identical assembly.

The leak is either totally or mostly inside the house (i.e. not draining down into the wall itself) and seems to be coming from just beyond that little collar or whatever it is that is near the wall when the assembly is in place.

 

[johnjh2o]

You can and should use a PVC trap but use a tubular trap not a glued trap. To help you out we need to see what is behind the collar. There are a few ways the connection to the piping in the wall could have been made. Hopefully it's done with a lock nut and not soldered.

 

[dperry9]

Ok, well I appreciate all the help. I think the only real challenge here is going to be getting the nut at the back off. I felt back there and it is pretty rusted.

If it isn't soldered, and even with the rust, would you just recommend a heavy pair of channel locks and just trying to force the nut it until it gives?

 

[phishfood]

See what kind of picture you can get with your cell phone, maybe we can see enough to figure it out from there.

I agree with John, the Drano probably ate through what little metal or corrosion that was sealing the trap arm back there.

 

[dperry9]

See what kind of picture you can get with your cell phone, maybe we can see enough to figure it out from there.

I agree with John, the Drano probably ate through what little metal or corrosion that was sealing the trap arm back there.

Yea, I think this was a "last straw" scenario where I really didn't do anything that bad---it was just really rusted back there already. For all I know this is an original part to the house from 1948.

I'll try to get a picture but right now the escutcheon is blocking any view and it's rusted in place. I'm not even sure what's back there myself. It does appear to be threaded so I may have to just try to force it off.

 

[havasu]

I would chop, cut or hack the escutcheon plate out of the way immediately. Then, if the pipe appears to have threads on it, go get yourself a can of PB Blaster (a real good penetrating oil) spray the threads, and let it soak for a day before trying to unthread it.