Replacement for toto gmax fill

[Realt0r]

I have a toto one piece 6lpf toilet that has a korky fill valve that isn't working properly. I ordered a new part and they sent me the tsu18a which is supposedly the replacement. I installed it and cannot get the water level to stay below the overflow pipe. I have adjusted it down as low as it can go but it still doesn't work. Is there any other adjustment except for the screw?

 

[Terry]

Instructions are here

https://terrylove.com/pdf/ms604_installation.pdf

There doesn't seem to be a lot of adjustment other then with the screw at the top.

 

[Sponsor]

 

[Jadnashua]

Have you checked your water pressure? If it is exceptionally high, the valve may have trouble turning off. Anything over 80# should have a regulator on it. If you have one, it may be shot and need rebuild or replacement.