I've purchased this house last year, it is 53 years old and in excellent condition. This is only happening in the basement toilet. It's been a slow flushing toilet since we purchased the home. I've noticed sometimes it doesn't completely flush the first time. I've also noticed when someone flushes one of the upstairs toilet the water level in the downstairs toilet fluctuates.
Now the issue is the toilet will not flush at all. I thought it might be plugged so I plunged it to no avail. Water level doesn't drop.
Next I got a toilet snake and snaked the toilet, that didn't work and the snake came out clean every time.
It is an older style toilet, not a low flow toilet by any means.
I am wondering if the toilet is bad, or maybe I have a venting issue.
Advice please... Thank you in advance. Karl

When you say the toilet will not flush at all what do you mean? Does the water back up into the bowl and refuse to go down?
The sewer drain pipe the toilet connects to may have a blockage between this toilet and where it connects to the main sewer drain. If so everything else in the house may work ok.

How does this toilet in the basement connect to the sewer drain? Is your sewer drain below the basement floor, or does that basement toilet have a pump that sends the toilet waste upward to a drain pipe?

Some water fluctuation in the bowl is not unusual when another fixture runs a lot of water down the drain (like another toilet or washing machine) since the movement of water in the drain pipe can cause air pressure changes inside the sewer pipe and that is felt by the toilet bowl water. The vent is supposed to take care of this but it may not be installed completely right. Vents are often blamed and they do cause problems sometimes but there are other possibilities too. Do you know if the basement toilet was professionally installed or done by the previous owner/handyman?

If you've cleaned out the toilet trap with the plunger or auger then I'd think the toilet itself is ok, your problem is elsewhere, possibly a blockage in the sewer drain the toilet empties into.



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You are describing what happens when the pipe to the toilet gets filled with water, for whatever reason. It would only be a vent problem if there was no vent, and that would only cause the symptoms, NOT be the real problem.

The water fills the bowl and doesn’t drain. It will drain after an extended period of time, 4 or 5 hours.
The basement toilet connects below the basement floor, all other drains in the house are connected to the sewer drain above the basement floor. We have no pumps.
I do not know if it was professionally installed but presume it’s been there since the house was built. The basement floor has never been broken up and or replaced.

if you don't have a cleanout available, you will have to wait for the water to lower and pull the toilet so a snake wire can be run into the pipe to clear the stoppage.

The branch drain that the toilet is connected to must be blocked.

What is a branch drain?

I'm thinking that is my next step...

It's the drain that serves the basement bathroom and separate from the main house.