I discovered a leak this morning in the basement from the drain pipe that connects to the second floor washing machine drain. The pipe may service other drains, hopefully not toilet, but the water looked clear and didn't smell. Anyways it's leaking from both the top and bottom of a coupler (sorry I'm not a plumber but I'll try to post a pic if it lets me, it would be the part in the top where it's dark, red arrows indicate where the leaks are).

Considering it's just a drain pipe, you think something is blocking it that's causing the water to backwash, or is the joint compound just worn out? I don't know how a spot like that which doesn't really move or experience vibration would start leaking, considering it's PVC pipe. Will I need to open up that "service" cover and see if there's an obstruction that built up? Will just putting more joint compound around it help? What kind of compound should I use? Or do I need to break the whole thing apart, replace and re-glue, or can I use the existing pipe?

Thanks in advance.

 

I'm not seeing any purple primer stains, so it may be possible it also never got glued.
Joint compound is what's used on drywall not pipes.
That line may be blocked but that should not have caused a properly glued joint to leak.
Pipe Cement, Primer & Cleaner - Plumbing Accessories - The Home Depot

 

The red arrows are telling here. IF you are seeing leaking at the top arrow spot, then there is another problem. That piece looks to be a 45 degree bend to align with the wye and waste line below. I can understand a potential leak below, but above? If that is a leak at above arrow spot, then the 45 is either broken there, OR leak is coming from above and accumulating on the top of 45 bell.

 

Where the arrows are pointing.....not only is there no primer used.... I don't see any glue either.
When making a connection like that glue will run down.

 

Agreed, but I see a bend on that piece which indicates what appears to be a 45. If that is the case, there would be no glue above there, only below. If water is in top arrow area, it either is a broken 45, or a leak above.

 

The pipe should be cut out and replaced using no-hub couplers.

Cut the bottom pipe above the wye hub, leaving about 2" of stub to connect no hub.
Cut the top in the area of the line.
Purchase and cut a short section of pipe. Cut the pipe just a little shorter than the total length you need to fill.

Loosen the jackets of the hubs and attach them to existing cut pipe at top and bottom, fully seated.
Slide the metal jackets away from the rubber, fold back rubber and insert the short section of pipe.
Once pipe is inserted, fold the rubber back down and slide the metal jacket back over the rubber.
Tighten the no-hub screws to 60 inch pounds.

Edit: I see it was pointed out the top is an elbow. You will need to cut above that to get to pipe. Is that possible?

 

They may be lucky in that there is no glue at the fitting and it may just come apart.

 

First of all, I want to thank everyone for the replies, I sincerely appreciate it on a Sunday afternoon. As I mentioned I'm a novice at home repairs and rely on forums like this and other sources on the internet such as YouTube to see if I can delve into these issues on my own. I noticed Pete replied too as he's aware of my fridge woes in the refrigeration forum, which is related to my fridge problem as I was making room for a new fridge since I could not repair my old one, so the new fridge is larger and to make room for it, I needed to make space for it by removing the baseboard, and it turns out, I caused the leak because in the process of prying out the baseboard, I must have moved or cracked what little glue was in that joint at the top of elbow where it meets the straight pipe. To me, it's kind of strange for such a pipe to be so close behind the drywall that any movement like that could affect it, which is the reason why they put some of that spray insulation to tighten the area, which I completely removed in making that small incision where it leaked at the baseboard (see my new pic below).

In my rush to post the first picture in my original post, the top red arrow was incorrectly drawn (so my apologies for that as it may have thrown some of you off), as that was just part of the bottom part of the elbow, while the bottom red arrow correctly showed the bottom joint of the elbow, the top of the elbow was actually up into the first floor, right behind the baseboard I just removed, because when taking a closer look, I noticed the drywall behind that baseboard was recently wet when my wife was running the clothes washer on the second floor.

It's not shown in the second picture I just attached, but there was little or no glue because I only saw very little purple primer just above the top of the elbow (which is the actual top of the elbow I posted in the first pic) where it met the straight pipe coming from the second floor. For some reason, that's where the seepage was, and as you can see by the picture rather than adding glue, which I'm sure most of you would have recommended, or use a rubber coupler with clamps which Handyone recommended, I ended up using a $4 tube of epoxy putty, EP-200 by Rectorseal (funny name brand) and kneaded it all around the joint tightly as shown in my updated picture here as a "quick" fix.

Hopefully that will hold as it claims to set as hard as steel in 15-20 min., though probably brushing some PVC compound would have done the trick but I wasn't sure if I'd make things worse by making that joint irrepairable (much like when I mess up things putting too much superglue), then I'd really have to replace everything. So I thought I'd try the epoxy putty first, and if it doesn't hold, I'll clean it all off and try the PVC cement. I'll probably leave that hole open to monitor it, along with the spot where it leaks to at the basement floor, as my new fridge is completely covering it anyways .

Thanks again everyone for all your help. Reading all the replies I was encouraged to troubleshoot some more and find the actual spot (hopefully it is, and nothing else leaking from above). Sorry for the misleading picture the first time, again, me being the novice handyman that I am, but I do make it a point to post follow-ups for my progress for all the time you guys spent to help me out.

Sincerely,
Paul

 

You have full access to the pipe above and below the floor. I would highly recommend the no-hub couplings. They do not need monitored for leaks, you fix it once and you're done. I wouldn't trust any other repair.

If you need specifics, we are here for you. Everything can be done with little tools. The only tool that would make the repair easier is a multi-tool to cut through the upper pipe which has no room for a hacksaw.

 

I agree with Handyone. You need to be careful what you do as you can make matters worse. PVC glue, for one, will do absolutely nothing on the outside of the bell joint, as it is intended to actually melt/fuse the PVC together. The epoxy was a waste of time and money as well.

The fix is much easier than you may think. You simply cut the straight section of pipe to remove the broken, not properly glued?? section and slip the no hub on. Tighten clamps and you are done. These no hubs are even approved for direct burial so you won't have any issues there. You may actually need two, as I can't quite tell where the elbow is. You really have no way to "reglue" a joint with PVC.

You want a square cut though, and given limited space I would use a wire saw. They are really cheap, and used correctly cut through that like butter.

Looking closer at the new photo, that is the top of a 45 elbow. I would cut the pipe in newest photo about 2-3" above the wall sill. Cut the pipe about the same distance below the elbow in basement. Now buy a 45 elbow, and a short piece of what looks like 3" PVC. Measure carefully the distance to the elbow. Prime and glue the PVC upper piece to elbow and from below push up to meet pipe in kitchen. Cut pipe as needed to align below and come flush to uncut upper pipe. Now add no hub coupler to the top. Measure and cut the bottom, PVC and glue to the bottom elbow. Add no hub there and you are all done.

Make sure you prime then immediately glue PVC, no wait time between. Push pieces together hard and hold as they will tend to push themselves apart until glue sets. For 3" this is usually about 20 seconds or so.

Good luck.