View Full Version : Toilet Flushing causes pipe rumblings

04-09-2007, 10:25 AM
I have a question regarding what happens when I flush the toilet in my Master Bathroom. I notice that when I just flush the toilet, with nothing in it, the pipes don't rumble......but when I put anything in it, like tissue, etc., the pipes rumble for about a second. Now I notice the same thing is happening with my other bathroom on the same level. Any thoughts? I was told by others that it may be a bad fillvalve in the toilet tank and possibly a bad stop cock behind the toilet. Since I was planning to do so anyway, I went ahead and replaced the WHOLE toilet in my Master Bathroom. I also replaced everything inside of the tank. I even replaced the stop cock (stop valve) with a quarter turn stop cock. I made sure I checked for leaks after installation....everything looked fine. Much to my dismay, when I flushed tissue down the toilet, after all of the issue goes into the toilet, I hear the same thunderous rumbling in the pipes (which lasts about a second). Any thoughts?

04-09-2007, 11:09 AM
Sounds like the problem is in the pipe(s) leading to the toilet. They either need to be secured better or you need a water hammer arrestor installed.

04-09-2007, 11:28 AM
That sounds like a wall will have to be broken, am I right?

04-09-2007, 03:00 PM
A hammer arrestor only helps a banging when the water shuts off quickly, it has nothing to do with things while the water is running, especially if you replaced the fill valve assembly and it is working. It is possible, if it is defective that it could be a washer vibrating, but it would have no difference whether there was anything in the bowl or not.

If there is a partical obstruction in the drain, the restricted flow could possibly be heard as things try to get by. You might try a toilet auger.

Does the toilet drain well, or is it a little slow?

04-09-2007, 06:37 PM
Make sure the closet stop is wide open. That washer could have come loose and does a little chatter.

04-09-2007, 07:18 PM
Water is heavy. Real heavy. Pipes don't rumble when water goes down.

Add one square of bathroom tissue, and pipes now make rumbing noise.

Is that it?


04-09-2007, 07:23 PM
Is this "rumbling" coming from the drain pipe or the fill line that attaches to the stop valve?

04-09-2007, 07:29 PM
In the first post, it says it only makes the sound if there is something other than just water in the bowl when it is flushed. Assuming that is true, it sounds like an obstruction in the drain. If it was the supply, it wouldn't matter. Now, if that is just a coincidence, who knows.

04-10-2007, 06:22 AM
With regards to "Does the toilet drain well, or a little slow?"
The toilet drains pretty well. I can see no indication of there being any blockage in the pipes, by watching the bowl empty. It drains just as fast as any other "normal" toilet that I've seen.

"Make sure the closet stop is wide open."
So the closet stop SHOULD be wide open? Well, I initially had the closet stop (1/4 turn stop valve) wide open after I installed the new toilet. It is now "half open".

"Add one square of bathroom tissue, and pipes now make noise. Is that it? "
It normally takes a lot more than a square of bathroom tissue to hear the rumbling in the pipes. Think of the average amount of paper a person would use for a #2.

"Is this "rumbling" coming from the drain pipe or the fill line that attaches to the stop valve? "
I'm pretty sure it's not coming from the fill line. I believe it's coming from the drain line.

I tried something last night. I had someone flush the toilet (with the amount of tissue one would use for a #2 (on average))while I stood in the dining room which is right beneath that bathroom. The toilet was flushed and I listened. I can hear the water running through the pipes for a good 2 seconds and then I hear that rumbling sound (which doesn't last very long). It sounds almost as if someone dropped something heavy on the pipe or in it. If you're standing in the bathroom when you flush the toilet, you know instantly that the noise is not coming from in the room, but definitely somewhere beneath you.

04-10-2007, 10:28 AM
Now that we know that this is a drain issue, you surely must have a problem with either the main drain pipe, or possibly a clogged vent.

04-10-2007, 10:57 AM
If it were mine, I'd open the dang shut off valve all the way regardless.

Do you have extreemly high water pressure ?

If you want to take one more step, tale that supply valve apart and see if the rubber inside is solid and not partially loose. Be prepared to replace that washer. A sloppy washer can create a vibration and a ballcock can also rumble and sometimes it sounds like it's somewhere else in the water line. Open that valve all the way.

I think the toilet paper issue is going in the wrong direction.

04-10-2007, 12:53 PM
" Now that we know that this is a drain issue, you surely must have a problem with either the main drain pipe, or possibly a clogged vent. "
Is there an easy way for me to check/fix it myself, or would I have to get a plumber?

" Do you have extreemly high water pressure ?
If you want to take one more step, tale that supply valve apart and see if the rubber inside is solid and not partially loose. "
I wouldn't say the water pressure is extremely high, but it's no slouch either.
The supply valve is brand new...should I still open it up?

04-10-2007, 03:16 PM
If I understand you, you replaced the valve IN the toilet. What is being suggested is to either replace or repair the shutoff valve at the wall. If this is a multi-turn valve, you might want to just replace it as well with a 1/4-turn ball valve (they look the same, but only take 1/4-turn between on and off and work better, longer). If it isn't a 1/4-turn valve, the washer in it can sometimes vibrate when water is running. The 1/4-turn valves don't have the same type of seals in them.

04-10-2007, 07:59 PM
I even replaced the stop cock (stop valve) with a quarter turn stop cock.

He's replaced the shutoff valve already. You guys ain't paying attention. ;)

I've had this rumbling sound in my drain before. The drain for my black water came out on the side of my rental trailer, where my neighbor kept a pit bull tied up. The dog would sometimes dislodge the pipe from where it tied into the main drain and the end would be flush against the ground. The rumbling was due to the water and sewage trying to escape and the air trying to displace it.

One thing you, Maximus, can try is to go on the roof and locate the vent for the toilet and see if it's covered with leaves or something. You can also try flushing it out with a garden hose. If that doesn't get it, you need to find the right clean out and snake the heck out of your main drain. Or, better yet, get a plumber to do it.

05-14-2007, 06:57 PM
Man, thank goodness I found this forum. I thought I was going crazy. I have the *exact* same problem. I had a plumber come out today to look at it and $177 later it's still not fixed. He suggested I cut a hole in my wall and secure the pipe against a stud. This is fairly new so that sounds more like hiding a symptom than fixing the problem.

Anyhow everyone (on other forums) seems to think it's either water hammer or the shutoff valve and I don't think it's either because I've tried everything suggested.

The original poster describes my problem perfectly. Either of my upstairs terlets will cause the pipe in the wall downstairs to vibrate loudly for a second or two. It only does it if there is paper in it, regardless if the shutoff is open, closed or partially open.

I'm going to check the vent on the roof as was suggested by the gentleman above. Also, when you say find the right clean out, I think I only have one. There is a capped, protruding PVC near the front of my townhouse that I've had to have snaked before. Could I need to have it snaked again? Just out of curiosity, how would this cause the pipe inside the house to bang/vibrate?

Thanks so much, gentlemen. :D

05-14-2007, 07:23 PM
Both you and the previous person are referring to the DRAIN pipe rumbling, and most of the proposed solutions have to do with the supply pipes.

I saw on Jon Eakes web site (under toilets) an article describing rumbling noise when flushing, as being caused by a partial obstruction in the stack, probably where the toilet branch or arm connects to the stack. Then, waste water no longer slows smooothly but gets turbulent suddenly.

Adding more toilet paper would explain how the noise gets worse.


05-14-2007, 07:45 PM
What exactly is the stack? Is that the main drain?

I'm thinking I'm going to rent a pro-quality snake and drop it down one of the upstairs terlets to scrape the stack free of any obstructions. Could this hurt anything?

Thanks guys.

05-15-2007, 01:59 PM
Thanks geniescience i had the same complaint from a customer and Toto had no idea what the problem could be, but thought it might be the vent.

The stack is your vent line that is attached to your drain line and should be a pipe sticking up through your roof.
You can also try flushing water down from the top as sometimes you can have debris and it will wash away.

05-15-2007, 04:01 PM
Thanks Peanut. Have you ever heard of a clogged vent causing this? Can I drop a snake down the stack to try to clear up any possible debris?

05-16-2007, 05:25 AM
As i said i had a customer call with the same problem but no one had ever come across that not even Toto (or so they said).
They thought it had to do with a vent problem, but a partial block sounds right.
You can run a snake down the stack, but it may also be a horizontal pipe that braches off the main stack.