Leak at waste line, Help!

[KSPinMSN]

I want to preface this by saying that I totally understand that the appropriate thing to do would be to call a plumber and have them come out, but with the pandemic going on and us having some high-risk people in our household, we wanted to see if anyone had any ideas in the meantime that might help us. I would say that we aren't novices to DIY but haven't done much plumbing work.

I'm attaching a labelled picture that helps show where everything is. We're in Madison WI, for reference.

Our kitchen sink and dishwasher are directly connected to a waste plumbing stack in the basement via PVC pipe and a 3" Fernco. A wash machine and utility sink in the basement empty into the same waste plumbing via their own PVC junction.

Recently, there seemed to be a blockage between the wash machine/utility sink and the drain stack which was resulting in the wash machine waste water backing up into the utility sink. We snaked the pipe but didn't actually pull anything out of the pipe; however, the wash machine started draining normally again.

Shortly after and thus possibly related, the drainage pipe from the dishwasher/kitchen sink started leaking at the Fernco connection between the PVC pipe and the drain stack. The dishwasher is also making a high pitched whining noise. It's not leaking all of the water, just some of it. Additionally, when the sink is run, there is no leakage.

What would you suggest as next steps? Is it possible there was a pipe blockage that we pushed UP into the stack that is causing leakage when large volumes of water drain (i.e. just a partial block of the pipe, causing a bottleneck and thus stress on the seal between the Fernco and the PVC)? Should I try to snake from the opposite direction I did before - from the top of the drain stack, just below the Fernco?

I know that this is like trying to diagnose a heart attack over the telephone, but I'd appreciate any suggestions you can give me!

 

[Reach4]

I think you have a cleanout in a good spot. The setup isn't really right I think, because that copper pipe from above is a little odd.

But anyway, I suspect you need rodding through that cleanout, and you might as well have the guy rod to the street. Let the water drain down so there is not a flood when that cleanout is opened.

 

[Sponsor]

 

[Terry]

The copper line is most likely the vent for the washer.
Is there a vent on the laundry sink? There should be.

The leaking Fernco can be replaced with a Mission coupling with the metal wrap which prevents the pipes from shifting. They come in many sizes, some with a side for plastic, and some for things like copper or cast iron sizing.

 

[KSPinMSN]

Awesome, this is very helpful. I think we can order and install the Mission coupling and in the short (few month) term we can go without using the dishwasher until we're able to call someone in to rod the cleanout.