What I thought was that I should tell you, so if you were to find yourself sitting on your toilet, holding your float in the air, you'd at least have some idea of what to do. I'll try to explain as best I can what I did to fix my particular problem, but this is only going to fix this particular problem and not every problem imaginable. I just want you to know that it's really not that hard. Plus it's totally fulfilling. I can definitely attest to the sense of pride and accomplishment you'll get from taming a wild toilet ballcock, not to mention the money you saved by doing it yourself. And don't laugh about the ballcock. If you haven't touched it at this stage in your life, you most definitely will in the future. It's a part of growing up.
After I removed everything, I also realized I had a problem with the rubber ring and the whole ballcock area. It wasn't just the screw that was unhappy. Perhaps the pressure from the water was needlessly pushing on the screw...I have no idea, but regardless, it's kind of a good thing this happened because everything got fixed in the process.
First of all, you have to shut off the water. That way, you can unwedge your bottle of SPF lotion, and really get down to the meat and potatoes of the problem. My immediate problem was that blue screw. See it up there? That little screw tells the water to stop going because as the float (attached to the metal float arm there) lifts, it pushes down on the plastic buttony thing inside (oh hey! That's the ballcock!), and there you have it, closed. Oooh, lookit how scientific I'm being! What it's really used for is adjusting the water level in your tank, too. But I'm just telling you the stuff I observed. And this is what it looked like to me. All right, so the problem with the screw was that the threads were pushed in and stripped. Basically, my screw couldn't screw anymore. So it kept sliding out and the ballcock just thought, oh! You need more water! I'm just gonna keep on pumpin' then, don't mind me! (toilet talk is dirty on all sorts of levels)
What I hoped was that I could change out the plastic screw or maybe just the top. I had no idea what they sold for parts. And by "they" I mean, those stores that sell junk like that. Or the stores you think sell junk like that. Case in point, I immediately went out searching for my dream part. First, I went to Canadian Tire. It's closest to me, and I wanted to go the easy route first. Nothing. They had no toilet fixing paraphernalia that I could see and if they do, they also had no staff willing to look at me so I could ask them where it was. Then I drove to Walmart. They only had entire toilet tank kits. I looked at them for a while. Fondled them a bit. I thought, well, they aren't that expensive, but I don't want to install the whole thing, so maybe that'll be my fall-back plan. Installing a whole new system seemed like too much work, plus it was 3 p.m. and this whole project was already encroaching on my me-time. Finally, I went to Home Depot. I really should have started there. They had an entire wall of little parts and pieces for toilet fixing and I found exactly what I needed in less time than it took for me to walk to the aisle. Just that part there, the cap with the four screws. That's all. No metal arm, no fill valve, nadda. I compared it to the picture I took, plopped down my $5, and skipped on home. Yes, you read right. That was not a typo. It cost me all of FIVE BUCKS. You thought it'd be astronomical, didn't you? Nuh uh.
Now because I failed to take pictures of the actual process, I'll show you the diagram printed on the back of the fill valve cap (which covers the ballcock, just so we're clear and so I can say ballcock again).
So, following the directions on the back, I worked in reverse. First I took the old screws out (2), then I removed the top. Secondly, I unscrewed the float arm and removed that. Next, I removed the old rubber ring (that black circle up there) which I should mention was gross and sticky and almost completely disintegrated. Then, to install the new top, I did those steps in reverse. Placed the new rubber ring in, put piece 3 into the cap (that's part of the package instructions), screwed on the old float arm, placed the cap on the ballcock, lined up the screw holes, and screwed it on tightly. I finished up by turning the water back on and letting the tank fill up again, lightly adjusting that top screw (the one I had problems with on the old cap) until the water level was where it should be (there's a line on the inside of your toilet tank telling you exactly where, but it can be a bit lower than that, if you want).
Marvel in your accomplishment.
That wasn't so terrible, was it? Not that you'd need extra help or anything for that, but if you do, Google it (I discovered [after the fact] that there's a ton of great pictures over the interwebs that are actually pretty helpful), or you can check out the Home Depot Improvement book (I bought it for Idle Husband last year. It's just about in every aisle in Home Depot). It's super awesome, because it has super awesome pictures and comments. I've found that for most things (I've had to use it for, anyway) it's tons easier to look up your problem in this book rather than finding it on the internet (sometimes the internet has too much information, you know?). I hope that makes you feel a little less scared about what's lurking inside your toilet tank. Knowing it's not that bad is really half the battle, isn't it?