What happens if the flange knockout cap goes down the toilet pipe??

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tsosin

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I live in the city and I'm remodeling my upstairs bathroom. My flange knockout cap accidentally went down the 4in ASB pipe. How serious of an issue is this? What do I need to do to get it out? I've gotten some mixed answers. I had a plumber come and he scoped it out and found it to be about 1.5ft from the drop into the city sewer. He wanted to open up the sewer pipe and pull it out before it drops down. He said if I don't do so it may cause a ton of issues and require me to drill into the concrete crawlspace and cost thousands... but I also had another plumber to tell me that I could just flush it out and into the city sewer.

What do I do?
Thanks!
 

Jeff Handy

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This story does not make much sense to me.

I think the plumber with the sewer camera should have been able to grab it, or just push it through to the bigger sewer pipe, while he was doing the camera inspection.

And if the cap went almost all the way to the sewer, it must be smaller than the inside diameter of your sewer line.
So why can’t you just flush it all the way out?

Before it causes a logjam, by getting wedged in with toilet paper and poop.

Why can’t a sewer camera just bump it along for the final 1.5 feet to the city sewer?
 
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tsosin

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The plumber made it seem like pushing it the rest of the way would cause lots of issues later. It’s already in a big pipe and the only thing holding it back from falling in is gravity. Is it ok for it to drop?
 

Jeff Handy

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The way you are explaining this still sounds odd.

Ask the plumber to better and more fully describe his concerns, it seems goofy.
 

tsosin

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I think he might have been trying to scare me into hiring him. He opened the floor and said the cap is sitting right before the drop. He said that if the cap drops down then it could cause lots of issues.
 

Jeff Handy

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First of all, that is not 1.5 feet from the city sewer, unless your house is built directly on top of the street, which of course it is not.

That is 1.5 feet from dropping into your own sewer line, which is probably the same size or even bigger than that pipe right there.
By my eyeballs, that looks like a three inch drain.

Your main sewer going to the street is likely to be four inch inside diameter.

From there, it could be many dozens of feet before it finally joins the larger city sewer line, out under the street or parkway.

So maybe the plumber is afraid the cap might get caught on an obstruction in your sewer line, like a root intrusion, or a narrow spot where toilet waste is sticking and building up.

Depending how long it has been since he located it, the cap might be long gone, if you have run any other water down that drain.

If you are worried about it, it should not be very expensive to cut the pipe right there, retrieve the cap, and repair the pipe.

Or you can buy your own cheap inspection camera with a 30 foot snake on it, for less than fifty bucks.
Check on Amazon.

They usually have attachments to grab or manipulate objects, they attach to the end and you can see what you are trying to grab.

Most of them work with a cell phone as the display, but some have their own screen.
 

johnjh2o

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The knockout caps in the flange it very thin and lightweight. A shop vac may be able to grab it.
 

tsosin

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First of all, that is not 1.5 feet from the city sewer, unless your house is built directly on top of the street, which of course it is not.

That is 1.5 feet from dropping into your own sewer line, which is probably the same size or even bigger than that pipe right there.
By my eyeballs, that looks like a three inch drain.

Your main sewer going to the street is likely to be four inch inside diameter.

From there, it could be many dozens of feet before it finally joins the larger city sewer line, out under the street or parkway.

So maybe the plumber is afraid the cap might get caught on an obstruction in your sewer line, like a root intrusion, or a narrow spot where toilet waste is sticking and building up.

Depending how long it has been since he located it, the cap might be long gone, if you have run any other water down that drain.

If you are worried about it, it should not be very expensive to cut the pipe right there, retrieve the cap, and repair the pipe.

Or you can buy your own cheap inspection camera with a 30 foot snake on it, for less than fifty bucks.
Check on Amazon.

They usually have attachments to grab or manipulate objects, they attach to the end and you can see what you are trying to grab.

Most of them work with a cell phone as the display, but some have their own screen.
Thank you for your help. These are good ideas. Yeah, that makes more sense. That’s a 4in pipe. So you think it it drops down there it won’t cause any trouble?
 

Geofd

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I live in the city and I'm remodeling my upstairs bathroom. My flange knockout cap accidentally went down the 4in ASB pipe. How serious of an issue is this? What do I need to do to get it out? I've gotten some mixed answers. I had a plumber come and he scoped it out and found it to be about 1.5ft from the drop into the city sewer. He wanted to open up the sewer pipe and pull it out before it drops down. He said if I don't do so it may cause a ton of issues and require me to drill into the concrete crawlspace and cost thousands... but I also had another plumber to tell me that I could just flush it out and into the city sewer.

What do I do?
Thanks!
i would bite bullet and cut it out if those 2 45s go up to the flange cut after the 45s,remove the toilet, and pull that piece away from the wye look in and see if its close
 

tsosin

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i would bite bullet and cut it out if those 2 45s go up to the flange cut after the 45s,remove the toilet, and pull that piece away from the wye look in and see if its close
I would if the flange was still stuck upstairs but it’s not. If I understand you correctly, the 2 45s you see are where my toilet pipe leads to the sewer line beneath the crawl space. The flange went down the toilet around the first 45 and then down the second all the way down into the crawl space, then traveled down the slow gradient to the other side of the house.
 

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