Toto Ultramax Tank Not Filling Sufficiently

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Jinmalibu

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I have a Toto Ultramax (MS853113S) round bowl. I determined the tank is not filling all the way to the fill line on the overflow tube. The water line when the tank stops filling is about 2 inches below the fill line. The consequence is that the toilet is clogging frequently, especially when my 6 year old attempts to use half a roll of toilet paper.

There is a Toto Power Gravity fill valve installed. It has a white plastic top. Is there a way to adjust it?

The manual for the toilet says my particular fill valve is not adjustable. See p. 5 in the link. Appears I have the type B in the instructions and says not adjustable. The G-Max/Power Gravity manual, on the other hand, says to twist the top half of the valve counter-clockwise to unlock the valve, lift it up to the point where the water level is correct and then turn clockwise to lock. https://www.guillens.com/Toto/pdf/GMax FV manual.pdf

I tried to twist the top of the valve, but there is not enough room to twist it far enough to get it to unlock assuming that is possible. I was concerned about breaking the valve, but maybe I am not twisting it enough to unlock?

After looking at some videos, it looks like this fill valve has one of those white locking tabs installed down at the bottom of the valve? Can this be removed to adjust the valve or do I need to replace the entire valve now?

Any suggestions to resolve the problem?
 
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Jadnashua

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It appears that you have the Korky valve made for Toto. If you go to their website, it shows in more detail, how to service the valve. It should not have changed, but the thing doesn't change on its own. You might find that all it needs is a new seal and maybe a cleaning of the float. Also, make sure that the hose going into the overflow tube is not kinked, and is attached to the clip properly. If it is pushed down into the overflow tube, it can siphon things, and could be the source of the tank not being always full.

There's usually a clip that prevents you from adjusting the height. It needs to be removed before you can adjust it.

Korky 528T Replacement TOTO Toilet Fill Valve - Fits G-Max and Power Gravity Toilets -Easy to Install -Made in USA
 
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Jinmalibu

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It appears that you have the Korky valve made for Toto. If you go to their website, it shows in more detail, how to service the valve. It should not have changed, but the thing doesn't change on its own. You might find that all it needs is a new seal and maybe a cleaning of the float. Also, make sure that the hose going into the overflow tube is not kinked, and is attached to the clip properly. If it is pushed down into the overflow tube, it can siphon things, and could be the source of the tank not being always full.

There's usually a clip that prevents you from adjusting the height. It needs to be removed before you can adjust it.
Can I remove the clip while the valve is installed in the toilet?

Answered my own question. I was able to get the clip off and raise the fill valve. I think I opened it as far as it would go. It started making a whistling noise after a few adjustments so I stopped there. Water now fills almost to to the fill line mark on the overflow tube. Much higher than it was before.

I will let my 6 year old test it out and see if that did the trick.
 
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WJcandee

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Make sure you have it twisted fully back into the locked position. Sounds like you probably do.

It's pretty easy to unscrew it from underneath the tank. Then you can twist and raise and then lock it back into place, then tighten the screw underneath. Of course, you want to drain all the water out of the tank first, so it doesn't all run onto the floor when you unscrew the nut.

Of course, if this did the trick, you're all set.
 

Jadnashua

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FWIW, the valve shouldn't go out of adjustment on its own. Usually, when things are getting worn, the water level ends up too high, though, verses too low. There might be some crud in the float, and all it needed was a little cleaning. But, leave well enough alone, but watch it to make sure raising it doesn't cause it to run and dump out the overflow.
 

Terry

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The Korky 528 aftermarket valve with the white cap is not the correct fill valve for that.
What you need is the silver cap Korky which has the proper bowl refill.
So two issues.
Someone installed the wrong fill valve.
That fill valve is also adjusted to be at least an inch too low.

www.terrylove.com/korky

korky-quietfill-p600.jpg


korky_instructions_3.jpg
 
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