diagnose toilet bowl discharge problem

Old 04-07-21, 03:22 PM
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diagnose toilet bowl discharge problem

please diagnose toilet problem.
when flushing toilet, water tank level drops (appears to function ok) when flushed
toilet bowl does not drain out (water & waste remain in bowl as tank drains down)
if I dump a small bucket of water into bowl , the bowel water/waste drains out ok.

what is preventing bowl to drain out, when tank water drains down ?

Last edited by XSleeper; 04-08-21 at 03:06 PM. Reason: Corrected spelling
Old 04-08-21, 11:39 AM
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Does it happen every time? Does the bowl fit up with water as the tank drains into it? Is the flapper valve in the tank opening fully to allow a fast flush?

A soft clog can prevent the water from developing enough force to clear the bowl but will allow water to drain out slowly over time. Flushing with a full bucket can dislodge a soft clog due to the high volume of water flow.

Soft clogs are usually due to excessive amount of toilet paper (although they can also occur with a large solid lump of waste that does not fill the channel but cannot get over the hump of the trap.) A half cup of dishwashing soap can soften a soft clog in an hour or so.

A small toy or other item that does not block the channel entirely can also act like a soft clog. If you suspect that is the problem when the bowl is clear (and clean) use a plastic bag (like a bread bag) as a glove and feel around to try and grab it. (That is Rich Trethewey's idea from This Old House, not mine.)

A venting problem could also be the cause if it happens all the time (like even after a bucket flush clears the bowl and the next normal flush of water only drains slowly.)
Old 04-08-21, 02:58 PM
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If the toilet flushes OK when you dump a bucket of water into the bowl then the problem is not in your drain lines. It's usually that water is not properly entering the bowl. I usually see the problem when people use those blue/green in the tank toilet cleaners. Pieces can break free and clog the water distribution passages in the bowl.

Remove the tank cover and look inside when flushing. Does the flapper open completely? Is there anything blocking water from freely flowing out of the tank? Also, flush the toilet and look at how the water flows from under the rim. If water comes out of some areas but not others then something may be clogging the passage.
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Old 04-12-21, 06:53 AM
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problem happens every time . toilet tank flap opens ok, water drains ok. toilet bowel show some water flowing down inside of bowel.

my solution... bought new american standard champion 4 toilet, waiting for install.
my worry is that problem may be in roof vent which has not been checked.
Old 04-12-21, 08:12 AM
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How would the roof vent know when you used a bucket vs. a normal flush?

I would first look into the tank and be sure it was filling to the proper level. If there's not enough water in there, it's not going to flush completely. Adjust the fill valve.

Likewise, if the flush valve isn't opening fully or is closing too soon, not enough water will get to the bowl. It shouldn't close until the tank is nearly empty.


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