Blue plastic seal under clean out port

Old 12-25-18, 06:29 AM
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Blue plastic seal under clean out port

I want to snake my drain lines in my crawl space. After removing 3 different clean out plugs I found a blue plastic disc that is blocking my access to insert the snake. What is the purpose of this blue disc and how should I remove it? Is it ok to just pry it out with a screwdriver?
Old 12-25-18, 06:41 AM
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Hard to know from here what it is without a picture.
Old 12-25-18, 07:37 AM
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It's clean out plug. Not unusual. From a Google search for the same.

"Beneath their drain covers is a plastic or metal cap, also known as a cleanout plug, as well as a standard drainage pipe. That cap stops waste water from flowing into the cleanout, forcing it to pass directly into the sewage pipe. They also help to keep noxious fumes and dangerous sewer gasses from leaking out and help to keep pests and debris from finding their way back down."

for the full explanation see:
Old 12-25-18, 09:18 AM
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When you remove the test plugs/caps make sure you don't loose the plastic in the drain pipe. Sometimes I'll run a long deck screw into the center so I can get a hold on it. If it's a vertical pipe I'll also tie a string on the screw so the plug doesn't go down the pipe and cause a clog.
Old 12-26-18, 04:04 AM
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Can someone suggest a website that shows this plastic plug and a video of how to install? My searches only find the end caps.
Old 12-26-18, 04:56 AM
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There are several different types of caps. I think the OP has a knock out test plug. They can be put inside a pipe and other fittings glued over top. Most are end caps but are sized so other fittings will go over them.


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