Replacing a Toilet Fill Valve

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Aug 26, 2017
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Hi, I am replacing this part and I saw the video (on YouTube)

Unfortunately after I disconnect the water supply,. I am unable to remove the white nut from the old fill valve. The only tool I have is an adjustable wrench.
I just cant get it open. Any ideas on the right tool to use?

Also the shutoff valve at the supply doesnt work but I am not going to tackle that! It kind of stopped.


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If the adjustable wrench will open enough to fit the nut, you should be able to remove it with it. Remember, lefty loosey, righty tighty. That is look up at the nut, you need to turn it counterclockwise. A pair of channel locks can also be used.

They don't need to be that tight. It doesn't look like it from the picture, but someone may have used silicon sealer which "glued" it onto the tank.
If you’re not laying on your back looking up but rather just reaching your tool of choice under the tank, you will turn Clockwise to remove the nut.
Thanks. I think the wrench is not going around it completely. I have a 8" wrench, I was trying in the right direction .. will go get a bigger one.
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Get a pair of Channellock 430, 420, or 426 pliers. Or all three!
Okay we got it done and it works and the water levels look fine!

There is a small (2-3 drops in 2 hours) leak from the pipe join where the white thing was. Any ideas how I can seal that?


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If you're saying there's a slight leak coming out from the hole the fill valve goes into, (where the white nut was) either the new nut is not tightened enough, or the gasket inside the tank, which is on top of that hole, isn't positioned properly to make a secure seal

That bottom nut doesn't need to be super tight, but it has to be tight enough to force the gasket down enough to form a true seal
Thanks for the replies. So I just noticed this little white ring that I did not put on the bottom of the valve. Is it an important part and should I remove the valve and put it on and then put the valve back? There was no water leak visible overnight but it may have dried up it was so small.

Regarding the level both the dials on the valve are at max so to get more water volume I may have to raise the height of the valve? Again this requires me to remove and adjust and replace? The old one didnt use this as well.


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Did you reuse the old fill valve nut? the only "little white ring" in your picture is the new nut.

You can raise the fill valve by pulling up the light gray plastic ring on the fill valve body and pulling up on the black plastic fill valve top. The instructions that came with the fill valve describes all of this.
I didn't have an old fill valve nut being used. I dont have one now, the photo below shows the red rubber thing making contact. no leak now so maybe I can ignore :)

The fill valve height can still be changed after installation without disassembly? I tried but nothing moves if pulled. I didn't try too much because the manual explains a twist to unscrew to lengthen, which I thought meant it needs to be done before installation, but if you tell me it can still be done I will go back to fiddling with it.


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So, are you saying is that you just shoved the valve and the tapered washer into the hole in the bottom of the tank and the only thing holding it there is friction? You did not screw a white nut onto the bottom of the black valve? Your initial question was how to remove that nut, that is MOST DEFINITELY required? Take a picture like the very first picture that you posted.

If you did not install a nut like that you removed, then you have a major flood about to occur! And don't try to pull up on that valve until the tank is empty. On that style, you do not pull up on the light gray plastic ring, but you just rotate the top and pull up. That should have been done during installation like the instructions indicate. But I have been able to raise them after they are installed before. BUT DON'T TRY THAT IF YOU DON"T HAVE A NUT ON THE BOTTOM OF THAT VALVE!
I screwed a nut on the outside of the tank of course. I was thinking I additionally needed to do that on the inside as well. Apologies if I was confusing.
Yes correct. On the outside I put the old nut on, using the new tools I bought after the battle to get it off.