Plumbing Question

[R Q]

My house is old built in '53 and kitchen sink drain lines are stopping up back in to the double sinks. So yesterday I took apart all of the white plastic pipes checked for issues, all were clear, The hard line under the sink is old galvanized so I looked and poured pitchers of water down and it was draining but I snaked them out anyway with a power drill type snake that had 50' of line on it. I felt no stoppages. Put all pipes back together and the sinks still backed up and don't drain for a long time. This old plumbing has no vent pipe but it has always drained just fine!
NOTHING has changed in the kitchen, under the house, etc. I suspected that possibly the dishwasher drain line that empties into the white plastic pipes may have been acting as a vent and had an effect but dishwasher works fine and I called a friend who does appliance repair to ask his thoughts and he said the DW drain has a check valve in it so it should not be the cause.
What in the Hell? I know there is an issue but all lines are clear and it has worked fine for years, even with different sinks and drain pipes!
My only thought is that the dishwasher drain has something to do with it?
Anyone ever ran across this?

 

[Caver Dave]

Did the 50' snake get you all the way to the main waste stack? (hard to believe it could be farther away than 50', but...)
What about the p-trap, run the snake thru it too?

 

[shawn]

It's stopped up somewhere.

Was the snake big enough to clean out the galvanized pipe, or just poke a hole through?

 

[Caver Dave]

Was the snake big enough to clean out the galvanized pipe, or just poke a hole through?

This too^^
@RQ, you'll have to ask @Tater about the escapades on his RV shitter

 

[R Q]

@shawn and @Caver Dave The only place the snake had any kind of slow down was at the 90 down under the house. Galvanized does not have a P trap, just a 90. Galv is 2" and the snake end was probably 1" and went through easily.
I can pour a lot of water down the galvanized pipe with no backup at all but when I put white plastic pipes back on I run water for moments and it starts backing up in the sink. This is crazy, I've looked through all of the white pipes and they are clear.

 

[Ron]

Tudor vent under sink or true unvented?

Any chance the sink goes to a gray water drain yard as opposed to the septic? If so with all the rain maybe its saturated. Wouldnt explain the difference between open and connected except maybe more air pressure overcomes saturation

 

[R Q]

Tudor vent under sink or true unvented?

Any chance the sink goes to a gray water drain yard as opposed to the septic? If so with all the rain maybe its saturated. Wouldnt explain the difference between open and connected except maybe more air pressure overcomes saturation

No sink goes into regular drains to city sewer. No vent under sink at all.

 

[shawn]

Wouldnt explain the difference between open and connected except maybe more air pressure overcomes saturation

If there's no vent, and the pipe is filled completely with water at any point in the unvented stub, the water acts as a stopper. That would explain why you could pour all you wanted down the pipe when the trap was removed, but nothing would flow once the trap was connected.

 

[R Q]

Crazy. It has worked fine just as it is now for years!

 

[shawn]

https://www.jlconline.com/how-to/plumbing/maximum-length-for-fixture-drains_o

That should explain it. I'd try to find another cleanout downstream and probe it from there.

 

[R Q]

I think I will attach a hose to the DW connection on the white plastic and see if have it vented like that will let it drain

 

[shawn]

Crazy. It has worked fine just as it is now for years!

For all you know, there's a tree root downstream of the auger.

 

[No fries]

That big ass tree in your yard could have roots growing in the waste line past the house, does it go to the road or to the back of your lot.

I can't resist but to ask, if you tried the backpack leaf blower. LMFAO!

 

[R Q]

That big ass tree in your yard could have roots growing in the waste line past the house, does it go to the road or to the back of your lot.

I can't resist but to ask, if you tried the backpack leaf blower. LMFAO!

Waste line goes out front. and no, I didn't try the backpack this time!

 

[Futbalfantic]

It sounds from the description to me, the issue is between the main line and the sink.

OP states: hooked up sink doesn’t drain

Unhooked he can pour water in and it drains without issue.

Snake went freely for 50’

Does the house have any vent lines in it? Maybe one of those got clogged

 

[CasterTroy]

This old plumbing has no vent pipe but it has always drained just fine!

No vent under sink at all.

Even though you're convinced there's no vent to that sink, you're certain that on the roof somewhere above the area of that sink there's no vent on the ROOF?

When I was kid I watched a crow fly from my grandfathers shop behind the house, to the roof of the house and drop things into the vent pipe. It took years, but the sink stopped up one time. They removed the trap and snaked it all the way to the septic tank....nothing. Still wouldn't drain.

They finally took the snake on the ROOF and snaked from the vent thru the roof. Discovered the crow was hiding metal nuts in the vent pipe. Over the years the bastard had stolen more than 50 nuts, washer, bolts from pops and they were stuck just above the sink in the horizontal before the VTR

I would start by snaking from the roof.

 

[R Q]

Even though you're convinced there's no vent to that sink, you're certain that on the roof somewhere above the area of that sink there's no vent on the ROOF?

When I was kid I watched a crow fly from my grandfathers shop behind the house, to the roof of the house and drop things into the vent pipe. It took years, but the sink stopped up one time. They removed the trap and snaked it all the way to the septic tank....nothing. Still wouldn't drain.

They finally took the snake on the ROOF and snaked from the vent thru the roof. Discovered the crow was hiding metal nuts in the vent pipe. Over the years the bastard had stolen more than 50 nuts, washer, bolts from pops and they were stuck just above the sink in the horizontal before the VTR

I would start by snaking from the roof.

I cut this house apart in '97-'99 doing a complete gut and remodel. I've been under, over, and in every square inch of it, No vent pipe for the kitchen arae, in retrospct I should have put one in but really didn't know better at the time. It worked, why mess with it? lol I checked the drains downline on this same line and all are okay and flow well. There is a vent there but I cleaned it out a few months back due to a clogged bathroom tub.
I'm going to do some testing and more disassembly tomorrow and see what else I can come up with.

 

[DLOR]

I did a bathroom that had a crazy backup scenario. The sink would drain fine at first(like a random hand washing) but every night it would clog up. Then the next day it was fine again. Turned out to be wood chips in the drain line that would swell up when lots of water was used(like at bedtime when all fam uses sink to brush teeth and wash faces).
I’ve also had squirrels and birds drop stuff into the vent pipes to clog them up.

 

[YotaOnRocks]

Subscribing because I'm interested to see what you find

 

[RatLabGuy]

So, if it's a clog somewhere farther down the line (like near the main etc - wouldn't you have problems at your other devices?
How are the other sinks etc in the house?

Another dumb question, just to disprove @shawn 's theory - do you have the piing to bypass the trap under the sink, to hook it up trapless?

And a final thought - is it possible that all this time it has been venting backwards through the DW exhaust line (b/c maybe it doesn't have a proper check valve or something) and now the DW line is juuuuust plugged enough it won't backflow? Or that valve has magically started working

 

[RatLabGuy]

Even though you're convinced there's no vent to that sink, you're certain that on the roof somewhere above the area of that sink there's no vent on the ROOF?

When I was kid I watched a crow fly from my grandfathers shop behind the house, to the roof of the house and drop things into the vent pipe. It took years, but the sink stopped up one time. They removed the trap and snaked it all the way to the septic tank....nothing. Still wouldn't drain.

They finally took the snake on the ROOF and snaked from the vent thru the roof. Discovered the crow was hiding metal nuts in the vent pipe. Over the years the bastard had stolen more than 50 nuts, washer, bolts from pops and they were stuck just above the sink in the horizontal before the VTR

I would start by snaking from the roof.

I’ve also had squirrels and birds drop stuff into the vent pipes to clog them up.

I've always found it strange there are no screens over the vent pipes on the roof. I added some just to avoid these scenarios (after having a house that had an overhanging tree dropping crap in there)

 

[R Q]

And a final thought - is it possible that all this time it has been venting backwards through the DW exhaust line (b/c maybe it doesn't have a proper check valve or something) and now the DW line is juuuuust plugged enough it won't backflow? Or that valve has magically started working

This is what I'm thinking. Opening it back up later today and will report back

 

[BrianGreen]

Could be a wet vent (using another fixture vent upstream). Is everything else in the house working properly?

 

[shawn]

So, if it's a clog somewhere farther down the line (like near the main etc - wouldn't you have problems at your other devices?
How are the other sinks etc in the house?

It sounds like the kitchen sink is the only fixture on that branch. No mention of other fixtures, or how far it is to a larger line.

If the kitchen sink is piped straight out into the yard all by its lonesome, I wouldn't be surprised if it's just draining into a dry well, and the pipe and/or dry well have failed, which is causing the slow drain. If there's enough pipe there, you can add water for a long time without a trap and not have any apparent backups. If there are downstream fixtures, they'll gurgle or even back up if there's a clog downstream.

 

[CasterTroy]

I agree with Shawn. If that sink is truly trap-free, and routed to municipal sewer, then you would get the smell of 10,000 assholes coming up from that drain.

But then again, this house IS old enough to have a "house trap". If the overall direction of the sewer wasn't changed when the house was connected to city sewer it may still be there.

Sounds like you know your house Richard, does it HAVE a house trap? If not, I think Shawn nailed it