plumbing: weird main soil stack clean-out plug

[Rema1000]

Near the bottom of the main soil stack where I live, there is what should be the main clean-out.  It isn't "Y"-shaped; it's just an opening in the side of the vertical pipe.  It doesn't have a typical brass plug, but rather is covered by a steel disk, which is held in place by a wingnut.

I removed the wingnut and disk.  Behind the disk is a gasket, and what appears to be some kind of plug material, with the threads for the wingnut coming out from the plug.  It's sort of bluish-purple in color; maybe some kind of epoxy?  What is this stuff, and how would I remove it (and how would I replace it)?

[weaselnoze]

would this be similar to a sand mound?

[Rema1000]

Sorry, by "soil stack", I mean "the big black vertical main drain pipe under the toilet in the basement".

[NiceGuysFinishLast]

Not gonna lie.. I thought this topic said "weird man soil stack clean out plug"... had me going  for a second... haha.. sorry I can't actually be of use though..

[coll0412]

Rema the purpulish stuff is thread sealent that is used when they fit PVC piping....


Does it look like this?



Is the plug rubber, sometimes people use those rubber plugs that expand to seal stuff


Although I am still not sure of what you are working with here....

[starwalt]

... Behind the disk is a gasket, and what appears to be some kind of plug material, with the threads for the wingnut coming out from the plug.  It's sort of bluish-purple in color; maybe some kind of epoxy?  What is this stuff, and how would I remove it (and how would I replace it)?

Doesn't sound familiar to me at all. I'd call a plumbing supply shop on Monday and query them. Unless you know a plumber that will chat for free, the supply shops get questions all the time.

Surely the "plug" is secured in the hole somehow. It won't just go down the stack because of the plate or get into the flow somehow. If not secured, from what I interpret though, it could fall out onto the ground with the metal plate and wing nuts still attached.

Lose something down there?   I had an obstruction in my septic system that ended up being roots at the entrance to the septic tank. The tank service found it. Man what a hassle. That's one job I don't want to persue.

[Rema1000]

I need to get into the main drain to run an auger.  I was thinking that there may be a metal disk, trimmed to an oval shape, with a carriage bolt through it.  It goes in the hole in the pipe first, then has some putty packed around it; then a gasket and another plate are fixed on the outside of the pipe.  The gasket and outer plate would be the seal.  The putty would be just to fill the void between the two plates, so that area doesn't get full of muck.

...or at least that's my guess.  I didn't want to chip it out, unless I knew how to get it shut again!  Sounds like a plumber will need to be involved (if only to make sure it gets sealed-up again).