Toto toilet goes through a cycle 3-4 times a day there is a loud grinding noise

Is this a water input or pressure problem or a settings issue or?

Hi Pallard

If you are telling us that the toilet basically turns on by itself periodically throughout the day then I'm pretty sure that the toilet FLAPPER is defective and needs to be replaced. Here, toto toilets have flappers that usually need to be purchased from a toto distributer ( local plumbing supply store) or online.

To confirm my suspicion on the leaking flapper, take some dark food coloring and drop 20 drops into the toilet TANK only and then check the toilet bowl every 20 minutes or so and see if the color has shown up in the toilet BOWL. If colored water is in the bowl then replace the flapper as presented!

Back to you...

Mark

Yes I agree with Mark, If you don't have food color another easy way to check remove the toilet tank lid and see that tank is full mark the water level, close the angle valve under the tank wait for a while and see if the water level is below your mark this will tell you that Flapper valve is leaking easy to replace, good luck.

John

Well, I agree with Mark and John. However I am really lazy.

I just hold the float down until water overflows the overflow pipe. That gives me a very precise water level. I turn the stop valve off and come back 20 or 30 minutes later. If the water level is not still at the very top of the overflow pipe I know I have a leaking flapper.

Hi Guys! The only reason I would not recommend touching the shut off valve to the toilet is because sometimes the shut off valves are seized and can't be turned off, OR after turning off and on, they can leak at the packing nut behind the handle and for some homeowners that can be a REAL problem! Using the food coloring or any dye shows the same result without risking a leaker or issue at the shut off valve, at least until the fill valve needs to be replaced and well, then the homeowner simply has to deal with a leaker IF it shows up... ;)

Thanks!

Mark I agree with your method but I recommended my idea incase there is no food color, Thanks.

John