Toilet stops fully flushing

[Walther]

Have you done anything to modify the tanks such as added bricks to reduce the water usage? Have you lowered the fill valve to lower the water line in the tank etc.?

nope and nope.

 

[Walther]

Have you done anything to modify the tanks such as added bricks to reduce the water usage? Have you lowered the fill valve to lower the water line in the tank etc.?

no I haven't.

 

[Sponsor]

 

[Walther]

ok, thanks.

so the idea would be to pour 5 gallons of water straight down the pipe, and if it doesn't readily go down the pipe that would indicate some sort of issue in the drain system, correct?

 

[Cwhyu2]

so the idea would be to pour 5 gallons of water straight down the pipe, and if it doesn't readily go down the pipe that would indicate some sort of issue in the drain system, correct?

yes that would be correct.

 

[Walther]

yes that would be correct.

Plumber came out today, pulled old toilet, and we threw a few gallons of water directly down the drain pipe with no issues. He put on new toilet and it works, so we'll see how long it lasts. The plumber agreed with posters here that the issue would not be venting, but he has no other solutions if I end up with the same problem again down the road (i.e., the toilet eventually stops fully flushing).

 

[Jadnashua]

If the performance is intermittent, it still could be a clog further down the pipe. Most of them tend to not be a complete clog, and the water drains out slowly. Depending on what was dumped into the drain previously (say you emptied a tub or had a long shower), you may have nearly filled up the pipe, and then dump a toilet load down, and it cannot accept it since there's no room. Later, after things have drained, it may work fine.

 

[Walther]

If the performance is intermittent, it still could be a clog further down the pipe. Most of them tend to not be a complete clog, and the water drains out slowly. Depending on what was dumped into the drain previously (say you emptied a tub or had a long shower), you may have nearly filled up the pipe, and then dump a toilet load down, and it cannot accept it since there's no room. Later, after things have drained, it may work fine.

The problem is not intermittent. What happens is that a new toilet will work "ok" for a while, and then stop flushing all together. Have gone through this cycle with 3 toilets over 25 years.