I needed to replace the flapper on my fairly new TOTO toilet. I turned off the water on the toilet and did the replacement. I turned the water back on. I was not sure how many turns on the knob I should so I just turned it what seemed right. As the water began to flow back into the tank there was a loud screeching noise from the pipes. The noise only stopped when I turned the knob until only a trickle of water flowed into the tank. Now it takes a very long time to fill up the tank between flushes. How can I correct this?