February 4, 2014
The fill valve in my tank is made by R & T. It's a standard fill valve (blue and white in color). The fill level is adjusted by turning the plastic shaft on top of the float, clockwise to raise the fill level, counter-clockwise to lower the fill level. The plastic shaft is white and has the shape of an "X". It makes a clicking sound as you turn it. It does not turn freely (so it keeps its setting), but you should be able to turn it with your fingers. You should not need pliers or tools of any kind. It is possible that you have mineral deposits if you can't turn it by hand. This could be problematic...forcing it with pliers is risky because it's all plastic. I have mine adjusted just below the top of the fill tube, but above the fill line, and the toilet functions flawlessly.
I purchased this model about 2 years ago, so the fill valve being used today could possibly be different, but all standard fill valves have some type of fill mechanism. If you have a different model, try googling it to see how to adjust it. Good luck!
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