Toto G-Max Fill Valve issue

Hello I have a Toto G-max toilet with Type A Fill Valve. It looks like the water continuously runs in the overflow tube. I tried adjusting the adjustment screw and seems to work for few seconds and then it starts filling the overflow tube. Sometime, when I press on top of the fill valve or pull the fill valve up slightly that seems to stop it. However, don't want to be doing this all the time. Do I need to replace the Fill Valve or is there an easier fix?

Appreciate it,
Sunil

The only servicing you can do on the Type A is to clean the screen at the bottom. Link to Servicing Instructions This usually helps with the tank not refilling enough or quickly enough, which isn't your symptom. (Here are the servicing instructions for the type A and type B: Ooops, looks like Terry has blocked this particular plumbing supply's web site, so the link to the servicing instructions that I usually provide is now dead. Sorry.)

I would just replace it with a Korky MaxPerformance 528MP fill valve, the one with the silver cap (the other versions of the 528, with the red, blue or white caps, don't have the right refill ratio for your toilet; the 528MP is adustable). (If you have the G-Max, like an original Drake, you can also use the 528T, which is set at the right refill ratio for GMax and Power Gravity, but not for any other Toto toilet flushes, like the E-Max. It's more expensive, though, so if you can get the 528MP, it's probably the move.) Available at Lowe's and other fine retailers:

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

Korky makes the Type B for Toto, and also makes a universal Toto replacement valve, which is basically a 528MP but is more expensive. It is number TSU99A.X.

Video on how to install the 528MP:


Good luck and let us know if you have any other questions.