very bad clog, must be in main horizontal waste pipe

[AcidWater]

Double kitchen sink, the undersink pipes are clear. Plunger no effect (while blocking the other sink). Liquid backs up to strainer after 4-6 cups. Really slow drain down to U.

I put enzyme dissolver in every night for several days, using a lot of volume since most of it remains in the horizontal pipe
between the two sinks and the drops and the U trap. No effect.

Kind of afraid to use something like lye crystals because of the large volume I need to fill the under-sink piping and then maybe a couple inches into the stainless steel sink, to create a bit of head. Maybe drop it directly into the downcomer pipe?

What are the odds the clog is in the approx 2 foot long downcomer between kitchen & main horizontal pipe (in the basement overhead)?
The idiots who remodeled the kitchen glued a 90 elbow to the top of the copper kitchen downcomer, so I cannot see or stick a stiff rod down it.

There is a Y cleanout on the stub end of the main horizontal (in the basement overhead) to the left of the sink, then a long length to a 90 degree turn (why is it not two 45s ?) with a shorter run to the main vertical to the septic tank. That last leg joins the hall bath, which is not backing up.

What are the chances that the 2" copper horizontal is just fully sludged after 60 years? Hate to have to replace all that, mostly
getting the shelves and boxes in front of the shelves away to access it. No empty place to move all that junk to

 

[Reach4]

What are the odds the clog is in the approx 2 foot long downcomer between kitchen & main horizontal pipe (in the basement overhead)?
The idiots who remodeled the kitchen glued a 90 elbow to the top of the copper kitchen downcomer, so I cannot see or stick a stiff rod down it.

If downcomer means vertical pipe, then pretty good.

What can you see and access from the basement of the place where the drain pipe switches from vertical to horizontal?

 

[Sponsor]

 

[AcidWater]

Downcomer = vertical pipe. I can't see the main waste horizontal due to stuff stacked up against the wall. Getting over an operation so I can't lift stuff or climb on a step ladder yet.

Does sludge tend to accumulate in a pile where a vertical drops stuff into a horizontal? I could cut off the stupid 90 elbow to access the downcomer beneath the sink & probe & put lye in it. OTOH I used a lot of the enzyme stuff and it would be right there on top of the pile... And why didn't the plunger shift it ?

 

[Reach4]

Does sludge tend to accumulate in a pile where a vertical drops stuff into a horizontal?

Yes.

The pipe under a kitchen sink tends to clog where it transitions from vertical to horizontal. I took a segment out of the vertical pipe, and cleaned from there. I used a Brasscraft drain bladder, but there are other brands. I pushed the hose thru and below the sanitary tee for the laundry, so the water was not backing up. I turned on the water, and let it do its thing.

After cleaning, I restored the segment with two Fernco couplings. While I used unshielded, I should have used shielded.

IN my case, the horizontal was under the basement floor, so there was lots of vertical pipe that was accessible. If your horizontal is up at the floor joists, that method would not work for you.

How about a diagram of how you think your drain pipe routes?

 

[AcidWater]

The internet ate my post...
in basement overhead, horizontal main line, copper 2 1/4" OD. Goes about 100 inches rightwards from where the sink drop enters, to the 90 deg left and the maybe 10 feet to the main vertical to the septic. To left of sink drop is a couple feet ending in the Y cleanout. Sink drop is 2 feet at most, copper. That last 10 feet after the bend takes one of the bathtubs, so only two feeds go into this line.

 

[Reach4]

That pipe would be 2-1/8 OD. The transition from vertical to horizontal should have been a long sweep with current codes.

You could cut a section out of the horizontal copper pipe. Rod toward the bend to clear the blockage. You could rod both ways, but expect the clog at the elbow. Then put the same piece that you cut out back, using two shielded Fernco 3003-22 couplings. https://www.menards.com/main/plumbi...g/3003-22/p-1444430435752-c-1478181399646.htm

https://www.supplyhouse.com/Fernco-3003-22-2-x-2-ProFlex-Coupling-Copper-to-Copper

If you wanted to make this easier in the future, you could add a cleanout.

 

[AcidWater]

As I said, there is a Y cleanout on the left end. I will not do the job, I'm too old & I have a reliable plumber at $140 an hour around here. Built in 1966, so I also wonder if the copper has gotten thin and might not withstand a roto-rooter attack. I think I'd rather replace it if there is a chance it would leak onto all the stuff below the pipe & get behind the shelving.

 

[bigb56]

I've cleared a few clogs by putting the garden hose to the drain with a wet rag wrapped around it to make a tight seal while holding in the other sink stopper in. An assistant then turns on the garden hose. You can also use a trigger sprayer if no assistant is available. If the clog is really stubborn the vent stack may fill up and water will shoot out on the roof. If you try this make sure your slip nuts are all tight so you don't blow the plumbing under the sink apart. If it works you will feel it when the clog breaks loose.

I learned this from an old timer when I was 14 and man of the house, it saved us more than a time or two. Not sure what a pro would have to say about it but it did work for me. Back then we had no extra money for things like plumbers, either I had to figure it out or we'd call a neighbor or someone from church to help.

 

[Reach4]

If the clog is really stubborn the vent stack may fill up and water will shoot out on the roof.

Out the roof is what would happen in this case. But to pressurize a pipe with a garden hose, a drain bladder is the tool.

A drain cleaning specialist would probably be the right solution, and a lot cheaper than replacing drain piping. On the other hand, acid water is not a good friend of copper.

If DIY, and especially if not wanting to address this from below, I would probably try putting a small electric-drill-powered snake down the drain pipe. Ridgid PowerSpin Plus 1/4 inch snake. https://www.homedepot.com/p/RIDGID-...less-Drill-Operated-Tool-Only-57043/303644607

I see that a 1.5 inch cylinder a foot long has a volume of about 5.9 cups. That would tend to indicate AcidWater's clog extend higher than the elbow in the basement.

Als

 

[AcidWater]

If DIY, and especially if not wanting to address this from below, I would probably try putting a small electric-drill-powered snake down the drain pipe. Ridgid PowerSpin Plus 1/4 inch snake. https://www.homedepot.com/p/RIDGID-...less-Drill-Operated-Tool-Only-57043/303644607

I see that a 1.5 inch cylinder a foot long has a volume of about 5.9 cups. That would tend to indicate AcidWater's clog extend higher than the elbow in the basement.
Als

If the clog is that close, I could try lye crystals. Its just that those idiots glued the plastic elbow to the downpipe under the sink, so I can't pour anything in it without sawing it off, which then renders the sinks completely unusable and the water too, unless I put buckets under the sinks.

Would a powered snake pass the 90 degree elbow? I'd want to just stick a flexible rod past the elbow and see how far it goes. Maybe Romex cable? No, there would be no "feel" to that. Piano wire?

 

[Reach4]

See https://terrylove.com/forums/index.php?threads/trouble-snaking-bathtub-drain.95143/#post-684357 #3.
I wondered if when the snake tip got to the sanitary tee, it would go up vs down. It went down.

How about a photo that shows your trap and the entrance to the wall. It might be that you could cut the current PVC trap arm near the wall, glue on a trap adapter, and use a slip-joint trap.