What's this black oily gunk in my drain?

I’ve tried looking this up by Google first, everything I’ve gotten says it’s grease, which I don’t think it is.

I have a sink in my laundry room, the sink is attached to the floor drain and I think the kitchen drain as well. All of my toilets and showers are on the other side of the house and not connected.

My laundry room sink is where my washer drains as well as the AC and heater. While I sometimes will wash paint brushes off and sometimes my hands after working on my motorcycle, nothing else goes down this sink. I never pour grease down my kitchen sink, nor do I really use the disposal.

I noticed my sink was over flowing when I did laundry. I tried using a plunger and it wasn’t really working. I figured I would just take the trap off and see what was stuck. Nothing was in the trap so I tried snaking out the rest of the pipe. When I pulled the snake out it was covered in a black oily substance. It looked, smelled, and felt like what would come off an engine that was leaking oil. I snaked it a few times and kept getting thick wads of the stuff, though the sink drained a bit better.

What is this stuff? I don’t think it’s grease as I don’t pour it down the sink, I don’t really get much of it when I cook. It also doesn’t smell like a sewer. I don’t go pouring a lot of stuff down the laundry sink, and I wouldn’t pour oil and such down there. I’ve lived here for 11 years and it’s only just started to do this. I guess the last person to live here could have poured something down there and it’s just now giving me problems.

What can I do about getting rid of it? My snake is metal so it’s not going to help I think. I’ve read they make other snakes, should I get one of those? Is there something I can pour down the sink to help? I don’t normally like doing that, but it might help. Or is this something I need a plumber for?

It’s bacteria.

Yeah what TheSundial said, microbial growth most likely. I believe there are products on the market for taking care of this situation specifically, if it is microbial.

OTOH a pic or two would help us help you

I’d agree with you normally, as that’s what others were saying, but this smelled like the grim I get off of my motorcycle, and the same consistency. It didn’t smell like a sewer as everyone else reported. I guess it could be, I’ve just never come across a bacteria that smells like oil before.

It does sound to me like the drains need to be snaked.

Isn’t that basically what oil is – ancient organic material decomposed by bacteria into a black, tarry liquid?

Congratulations! You now have your own (small) oil field growing within your laundry drains. Now just build a small refinery, and you can fuel that motorcycle yourself!

I think I’ve got a similar situation in my bathroom sink, I just thought it might be a buildup of the special soap I use to shave. Every so often I use a plunger on the drain when it takes an unusually long time to do its thing. I seal up the overflow port, make sure the sink is filled with hot water, then plunge the daylights out of it. Lots of dark,waxy blobs come up, and after awhile the drain is good to go(never 100% to my satisfaction, but whaddya’ gonna’ do?) Never been able to discern a smell.

Edward the Head: Maybe it’s just a buildup of grease and grime from your washing machine outflow?

I know this wont help but…

Once I pulled a pipe off my shower drain, it was clogged with the black goo. I tossed into the yard so I could try to clean it with the hose. My dogs got to it before I did, turns out dogs think the goo is tasty. I really like dogs but my opinion of them was lowered a bit that day.