Found the reason my toilet kept backing up - it was in there since before I bought the place

That story takes me back. We bought our 1948 ranch in 2011 and the upstairs toilet woud clog every couple of weeks no matter what we did. My wife was convinced it was the old cast iron stack slowing everthing down and we were budgeting for a repipe. Then one night my son admitted he'd flushed one of those plastic dinosaur toys years earlier, back when he was five. Sure enought, pulled the bowl and there it was, wedged sideways in the trap, worn smooth from years of water and paper hitting it.

What surprised me was how long it sat there without fully blocking things. It just acted like a speed bump that caught everything untill one day the stars aligned and it jammed tight. Sounds like your iron piece did the same thing for decades.

Funny detail from mine: the previous owner had left a note in the attic about the house that mentioned 'slow toilet upstairs, use thin paper.' He knew somethig was in there and just worked around it instead of pulling the bowl once. I did the same dance for two years before my kid fessed up.

We keep the dinosaur on the windowsill above the toilet now. My son is in college and still gets ribbed about it every Thanksgiving. Your rusty bracket makes a better trophy though, at least mine is plastic and didn't come apart in my hand.

I chased a similar ghost in my 1958 cape cod for almost two years before I found out the problem was never in the toilet at all. Ours would flush fine for weeks, then back up with no pattern to it. Pulled the bowl twice, found nothing, put it back, cursed a lot. Turned out the cast iron lateral under the basement floor had a section that had shifted where it met the clay pipe out to the street, and roots were threading in through the gap. The toilet was just the first place the backup showed up.

What finally cracked it was renting one of those push cameras from the rental yard for a Saturday. Seeing the root mass on screen after all that guessing was almost a relief. A guy came out with a rooter machine, cut them back, and we paid a plumber to line that joint the following spring. Haven't had a backup since, knock on wood. So for anyone else in an old house with a toilet that clogs on no schedule, if you pull the bowl and find nothing wedged in there, don't keep blaming the fixture. The trouble might be ten or twenty feet downstream where you'll never see it from the bathroom. A camera run is cheaper than a third toilet pull and a lot less cursing.

This makes me wonder about my own bathroom now. Our toilet has been flushing weak ever since we moved in and I always blamed the old pipes. I never once thougth somethig coud just be sitting inside the pipe doing this for years. I don't even know how you get the toilet off the floor though, is it just unbolted from the bottom or is there more to it? Might be worth a look before I spend money on a plumber.