GMax issue: won't shut off

I apologize if this question has been asked, I searched the list and didn't see any thing but could have missed it.

Here's my issue:

I have 3 Toto GMax Toilets all are about 7 years old, which I installed not long after I bought my home. Just this past week, one of the toilets began to fail to shut off when the water reached the fill line. I replaced both the replacement cap assembly and the flapper and neither item corrected the issue. The toilet tank continues to fill beyond the fill line. I manually lifted the float with my hand and the water does not shut off when I lift it to its maximum height.

What's the issue?

Thanks
Rod

While you have the assembly cap off, flush some water through the valve to make sure there is nothing like sand or grit still in the lower portion.

There is no other reason why the valve would not shut off if the tower adjustment has not been changed.

www.terrylove.com/korky

Hi:

I'm going through the exact same issue right now and did the same things you have so far. My flapper was definately bad. My Ultramax is the same age as yours too. I talked to Korky who makes at least some of these valves for Toto, and they said to turn over the black rubber pilot seal that covers the little hole in the cap when the float is raised by the water.

Instead of doing that, i'm going to try next replaceing the entire float assembly with a new float from the cheaper universal 528 "quietfill" valve available at Lowe's. I've confirmed that the replacement cap and the float are the same for both the 528 and the 528T assemblies.

If that doesn't work, there's probably a crack in the fill valve or a leak in the fill valve someplace other than the valve assembly (the R528 cap and the float) itself and you would need to replace the entire fill valve.

See here: https://terrylove.com/forums/showthread.php?t=25707 for more information and a link on where you can get the 528T for $16.09 + shipping. Also you might want to look at www.korky.com.

Let me know if you have more questions, I'm pretty deep into this problem already and I'm going to work on my 528T valve again this weekend installing a new float.

You did well replacing the cap! Once it's been on there for 6-7 years it doesn't like to come apart real easy. It seemed to help pouring hot water on the cap assembly both during dis-assembly and re-assembly. If you replace the cap and the float, that seems to me to be the entire valve, all the parts. If that doesn't work, replace the entire assembly.

Can you hear yours leaking? Most of the time my leak is so slow you can't even hear it. I did notice my water bill went up the last few months but I didn't know why. LOL

Hope this helps some! Let me know.

Lee

Terry said:

While you have the assembly cap off, flush some water through the valve to make sure there is nothing like sand or grit still in the lower portion.

There is no other reason why the valve would not shut off if the tower adjustment has not been changed.

www.terrylove.com/korky

Click to expand...

Thanks for the reply, Terry. To do this would I simply pour water through the top of the valve? I have pulled out the core of the valve assembly and it was clean. I ran some warm water on it but no changes.

I'll try flushing water through the valve.

lee_leses said:

Hi:



Instead of doing that, i'm going to try next replaceing the entire float assembly with a new float from the cheaper universal 528 "quietfill" valve available at Lowe's. I've confirmed that the replacement cap and the float are the same for both the 528 and the 528T assemblies.

Click to expand...

When you say to replace the float, are you referring to just the part that attaches to the assembly cap or more than that?

Also, can you let me know if the replacement of the float corrects the issue?

Check out my other post about the 528 and 528T using the link above.

There's a new link to pictures that shows the main difference between the two valves.

I'm not sure the 528T should cost three times what the 528 does, but I guess labor to install the flow restrictor costs a lot.

I will let you know if I find the leak. I should say WHEN I find the leak!

Lee

See the latest at:

https://terrylove.com/forums/showthread.php?t=25707

I ended up replacing the fill valve with a Korky 528T...

Lee

Lee

Thanks for the advice and assistance. I replaced the fill valve with a Korky 528T from the Ace Hardware Outlet you mentioned and all is now well with my Toto.

That's great!

It was all worth it in the end. I learned a lot, and I was able to help you a little too! As much plumbing as I did in the old days, I was still really afraid based on Murphy's Law that I would not be able to get it back together with no leaks. But all seems to have gone great.

Tell me, how much plumbing have you done, how worried were you about the job, and how smoothly did it go when you ended up doing it? I know this is lame, but with cleaning behind the toilet on the floor and draining the tank completely, I think it look me an hour.

Glad my source worked out for you too. I did a lot of Google before I found them. They shipped quick and I thought their price was pretty good too.

Lee