Diagnosing sluggish toilet flush

I am trying to diagnose a sluggish toilet flush. I want to determine whether it is the toilet, the stack drain or the vent.
I have four toilets in the house (three on the second floor), and this is the only toilet that has a problem. This is one of the second-floor toilets. It is an older 5-gallon toilet.
If I flush the toilet, I get a strong water flow into the bowl, a strong swirl, and a strong whirlpool. But no siphoning. The water level in the bowl remains high throughout the flush. When the flush valve closes, the swirling stops, and the water remains at that level, instead of emptying the bowl through siphon action.
If I keep pouring buckets of hot water into the bowl, one after the other, two bucketsful siphon empty, but every third bucketful leaves water in the bowl (at the normal, neutral level). The fourth bucketful drains empty again.
Fishing with a toilet snake, I cannot find any blockage in the trapway. I have not tried removing the toilet to fish from the bottom (that is a last resort).
What are your thoughts?
- David
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the
I
WAG something's in the drain pipe, like a towel or rag of sorts. Slows normal water flow.
Pull the toilet, sorry this is the only way I know of that will help the situation. Get a snake very close to the diameter of the pipe.
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David D. wrote:

...
Could be several things. I would consider a clogged drain beyond where your attempts at snaking has been able to reach being the most likely. You might be best off with a commercial outfit. Otherwise SQ had some good advice. Remember you will need a really long snake.
I would not rule out the possibility of a clogged vent as well, but I would not put that first.
--
Joseph Meehan

Dia duit
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David D. wrote:

maybe poor seal between toilet and floor pipe. Still remove toilet is the answer. I hear once you remove tem you gotta replace the seal anyway.
--
Thank you,



"Then said I, Wisdom [is] better than strength: nevertheless the poor
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David D. wrote:

    Although your solution might well be in the other answers you received, I would do a newsgroup search for the words: "Muriatic Acid" & "Toilet." I too had a toilet that was problematic in flushing and it too was an older type toilet. The toilet was apparently limed up and the acid solved the problem. Just thought I would alert you to the solution.
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As long as you have PVC or plastic drain lines carefully pouring some muriatic acid down the dip tube cant do any harm. Use a funnel and wear eye protection. If the passages in the toilet including the bowl rim are clogged this will fix it up
Cheap too its under 5 bucks!
drain bowl completely, plunge then use sponge
put in acid, wait 20 minutes then flush normally, you will know right away if its fixed.
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Unfortuantely, I have ancient, galvanized drain pipes. So it is even possible that my clog is corrosion buildup.
The branch drain from my kitchen sink is accessable from the basement, so I replaced that section with PVC -- What a difference! The old pipe was half closed.
But all of the other drains are inaccessable -- The stacks are in the wall and the sewer line is under a slab. There is a main cleanout in the utility room. Ugh! -- cleaning out from there would create a real mess. Besides, that cleanout is well beyond the junctions of all of the stacks (with no individual cleanouts). It could be tricky to fish a snake into the proper stack. Snaking from above, after removing the toilet, sounds most promising. Depending on the condition of the galvanized stack pipe, it might even need a roto-routing.
But, then, who ever said that plumbing is supposed to be fun.
- David
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Ken wrote:

...
I think the "If I keep pouring buckets of hot water into the bowl, one after the other, two bucketsful siphon empty, but every third bucketful leaves water in the bowl " rules that out. However I could be wrong.
--
Joseph Meehan

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With multiple buckets minor differences in bucket volume may introduce one poor flush.the fact that at least 2 are OK makes me believe it sediment buildup.
I would still try the acid, then flush 20 times, to make certain the acid doesnt lay in the cast iron pipe anywhere, run all faucets afterward.
or you could pull the toilet, take toilet outside, plug exit and treat with acid. then flush everything with a garden hose
no repair is risk free:( Pulling the toilet you might find the flange bolts are bad, or crack the flange if its corroded. these sorts of troubles make plumbing not fun for me:(
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Thank you, everyone, for your suggestions.
Whether I do it myself, or hire a plumber, it sounds like the most likely problem, and first thing to try, it to remove the toilet and fish the stack drain.
Ahhhh... An adventure beckons!
- David
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I had a lazy, slow flush in my rental house. I had never had a problem in 9 years of living there. I paid R***Rooter $435 to fix it which they did not. I created such a stink that they sent the regional manager out and put a camera down the pipe. Of course the problem was the plumbing they said. It would need a new sewer pipe installed. Not a trivial task with the house sitting on a slab. Wait a minute I said. You are full of the same stuff clogging my pipes. So I looked elsewhere. I found the notorious green goo. The cleaning company that cleaned the house prior to the last tenant moving out put those green tidy bowl tablets in the toilet tanks. One look in the bottom of the tank told me what I needed to know. Being a scientist by training I knew that for a toilet to flush properly, the water had to move fast enough to generate the siphon effect to pull the water and waste up over the trap to clear the bowl. The thick viscous goo was making the water too viscous to do that. A garden hose and about 5 flushes solved the problem. I first hosed out the tank then filled and flushed the bowl and the problem went down the drain.
I wrote to R***ter Rooter and told them they were a bunch of theives. They have to know from exprerience of this problem especially in old houses, and it has to be a bigger problem for low volume toilets. If my experience is any example they are making millions at the expense of consumers by omission. They know, they just don't tell. Instead, they charge $100s or even thousands for unnecessary repairs. Beware anything you do to upset older plumbing. As they say, if it ain't broke, don't fix it. As far as I know, appliances were designed to function with plain clear water, not with the additon of a thick green slimey goo.
Keith
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