How to raise water level in toilet tank?


Old 12-11-13, 12:58 PM
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How to raise water level in toilet tank?

How can I raise the water level in a toilet tank?

My Mom has a toilet that at some point has had the ball mechanism replaced. You can tell because the water level now is about 1" below the top of water stain on the tank's wall. The top of the stain is about 1" below the fill line embossed on the tank wall, which in turn is a further 1" beneath the top of the overflow pipe. And it no longer flushes hard enough to remove solid waste.

I already emptied the bowl and cleaned the build-up out of the holes in the underside of the rim, and cleaned out the blow hole, but that made no noticeable difference.

I don't know how the nomenclature for these things, so I figured a pic was in order:

The float adjustment long since is maxed out, the water is as deep as it will get, but it isn't yet deep enough. I put some large lead fishing sinkers on the float, which helped somewhat, but that still didn't raise the level in the tank to the high water mark, much less the max fill line, plus it had a tendency to stick once and a while, leaving the water running.

I thought about shortening the bit of plastic in the adjusting mechanism, which would raise the level the float comes to before switching off the water, but I'm concerned about the water-proofness of whatever I use to join it after having cut, shortened and spliced it.

I haven't bothered to check to see if a "taller" ball valve mechanism might be available because I figured in this low-flow era, they probably would only be even shorter. In fact, I figure that's what's wrong with this one. But low flow in this case wastes far more water than it saves because you commonly have to flush this one three and four times to remove all the solid waste.

Am I wrong? Is there variation in the height of the mechanisms available? Or can anyone think of a way to modify this one to produce a more effective standing water height?
Old 12-11-13, 05:16 PM
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Underneath the float on the shaft of the fill valve is a slip ring that holds the upper part of the assembly to the lower part. The lower part is screwed to the tank itself, the upper part is adjustable. Lift up on the slip ring and it should pop loose from its place. The whole top part of the fill valve can then be repositioned higher in the tank. Once adjusted, slide the slip ring back down until it snaps. Fine tune then with the adjustment on the float itself.
Old 12-12-13, 10:18 AM
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Fred I think this diagram indicates what czizzi is referring to. It would be the location marked “Adjustable Height” at the bottom left of the diagram at the top of this page:

Troubleshooting a Fluidmaster 400A Toilet Ballcock
Old 12-12-13, 01:02 PM
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You can adjust the water height by turning the small knurled knob on the right that has a + on the top. You'll see that the plastic rod below it has a spiral thread pattern that will raise and lower the float.

If that does not provide enough adjustment you can do what Crizzi mentioned just make sure to turn off the water to the toilet first. The plastic ring can be a bit stiff so I put one hand on top of the valve to hold it down while I pull up on the plastic ring with the other. Then give the valve a pulling, twisting motion and is should snap up. Then push the plastic ring back down to lock it in place.
Old 12-12-13, 02:57 PM
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WOW, gents, ya'll are all geenuses. I can't believe it was that easy. Thanks much for your help!

I got the water level back up to the original high water mark but not yet to the Max Fill line. Does the slip ring joint have a mechanical stopping point, or if I try to pull too far, will it come apart in my hands?
Old 12-12-13, 03:10 PM
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Does the slip ring joint have a mechanical stopping point, or if I try to pull too far, will it come apart in my hands?
It will stop as there is an O ring at the top of the riser...

You will not get it that high anyway because it will be sticking out the top of the tank....

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