Fluidmaster 400A problems!

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itsr-ent

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I just installed a new Kohler Cimmaron toilet that came from the factory with the Fluidmaster 400A (or similar...it's re-branded with Kohler's logo on the cap). The 400A doesn't seem to fully shut off...it has a very slight hissing sound and periodically squirts some water out from under the cap. This eventually leads to the water level rising enough to go into the overflow canister.

I took the top off, cycled the water on/off to clear out the valve. I even popped out the rubber seal and cleaned it well with hot water and again with isopropyl alcohol. It then worked fine for a few days, but is now doing the same thing.

I'm going to call Kholer for a replacement valve since the toilet is brand new, but I'm so frustrated with the 400A. This is the third one I've installed, and the 3rd one I've had issues with! Years ago I installed one to replace an old worn out ballcock and couldn't get it to fully turn off. Gave up on that one and installed another old school ballcock.

A few weeks ago I replaced my own toilet's ballcock with a 400A and also had the same issue! It just seems like the float doesn't make enough pressure to positively turn off the valve. I followed the instructions to flush it before even using it the first time, cleaned the seal, etc. After flushing it out multiple times and finally cleaning the rubber seal AGAIN, I have been able to get this one working for a few weeks now without further issues.

Every time I've had issues, I've verified there's no leak at the flapper (or canister in the case of this new Kohler toilet) by marking the water level in the tank and waiting an hour with the water turned off.

I finally got the Fluidmaster valve in the Kohler to work for now by slightly bending the end of the plastic arm that attaches to the float adjustment screw just enough to make it push at a little better angle. However, after a few days, it goes back to not fully turning off.

These 3 toilets have been at different homes with different city water systems, no well water.

Any ideas? I know Kohler will send a replacement, but I'm not going to keep battling with these things...pretty sure I'm not doing anything wrong with the installation or adjustment. Thinking about trying the Korky 528, but I keep reading that plumbers are installing the 400A by the case load and not having any issues. :( What could be wrong?
 
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Jadnashua

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Check your home's water pressure...if it is over 80psi, that may be the reason. Also, can you possibly correlate when they leak verses use of hot water? If you have a closed system (a check valve or a PRV in the system), when you use some hot water, the cold water that replaces it expands when it is heated...the pipes aren't elastic, so the pressure rises, and often a toilet valve can be the weakest valve in the house, and it leaks there. If you have a closed system and an expansion tank, but the expansion tank is shot, the pressure can rise through thermal expansion, increasing the pressure.

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WJcandee

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Plenty of the plumbers on here swear by the 400A.

However, Terry routinely recommends the Korky 528 for members on here, in part because once it is in, all you have to do 5 years from now to fix it is replace the little cap on the top, without taking out the whole valve. It's easy for regular folks to install correctly.

All seven toilets in our house now sport whatever 528 flavor is right for that toilet, and we have no issues.

If you have a new toilet, just go to Lowes and get the Korky Maxperformance 528MP, which has the silver cap. (Lowe's shows it on its web site, which has an atrocious search algorithm, as "528MPK".) This valve has a little dial on it that lets you adjust the refill percentage so the bowl will fill properly but not overfill and waste water. It is actually suitable for any toilet of any age that takes a ballcock or similar fill valve.

Korky (hokey/homey) video on how to install the 528MP. See? Easy!


PS The graphic in the video where it says "water level too high-- turn clockwise" is backwards; whereas the script she reads is correct. If the water level is too high when you flush, turn it counterclockwise a smidge to reduce the amount of refill water entering the bowl. If it is too low, turn clockwise. I have pointed this out to Korky and they don't seem to have fixed it yet.

PS As Jim correctly points out, if you have numerous toilet valves not being able to hold against the water pressure, your house pressure is probably too high. This is usually caused by thermal expansion during hot water heating, and more rarely by an un-reduced too-high City water pressure in the main. Check your expansion tank to make sure it's still working and if you don't have one, you probably need one. You can tell by checking your water pressure at a hose bib or laundry sink right after the water heater has finished running.
 
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itsr-ent

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I will check the water pressure...that is something I've been meaning to do. However, have had issues in 3 different homes (in 3 different towns), so I don't think they all have a water pressure issue! It's possible though...

No closed system, the houses I've done this work in (including mine) do not have a check valve or PRV.

I was doing some more research and found someone else's YouTube video that shows exactly what I'm seeing:


If you lift up on the float arm every so slightly (like 1mm), it stops and stays stopped until the next flush.

Will definitely go with the Korky 528 from now on for replacements, but not in the brand new Kohler...would like them to send me a non-defective part!

I guess it just baffles me that so many people are having the same issue with a product that is so popular and is the factory-supplied fill valve on a few brands of toilets! If I have to replace a 400A with another one, I'm going to buy 2 or 3 at Lowes and then return the non-working ones!
 
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WJcandee

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You can stand on principle, which I totally understand, or...

Like me, you can decide that you'd rather end the drama and wasted time, and put in a fill valve that works, and spend the $12 on a 528.

I'm guessing that if you do that on one, you'll go back to Lowe's and buy two more.

FWIW, the Korky is and has always been made in Wisconsin. The 400A is now hecho en Mexico. Maybe that has something to do with the reject rate. (Or maybe not.)
 

itsr-ent

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You can stand on principle, which I totally understand, or...

Like me, you can decide that you'd rather end the drama and wasted time, and put in a fill valve that works, and spend the $12 on a 528.

I'm guessing that if you do that on one, you'll go back to Lowe's and buy two more.

FWIW, the Korky is and has always been made in Wisconsin. The 400A is now hecho en Mexico. Maybe that has something to do with the reject rate. (Or maybe not.)

Thanks for the help, wjcandee! I'm going to at least pick up a 528 (the basic one is only $8.87 at Lowes) to have on hand. The new Kohler -- I would just swap to a 528 as well, but I installed the Cimarron for someone else and they want to stick with the Kohler parts...:(

This site is great! I have a supply valve question that I need to take a pic of and get some thoughts on replacing it. Thanks again everyone!
 

WJcandee

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Thanks for the help, wjcandee! I'm going to at least pick up a 528 (the basic one is only $8.87 at Lowes)

Yeah, the basic (white cap) one is only good for toilets that flush 3.5 gals and up (i.e. the pre-1994 toilets). It is set to a refill ratio of 20% (i.e. 20 percent of the water used to refill the tank is diverted into the overflow riser to fill the bowl). That was the standard in basically all toilets up to 1994. If you use it in a 1.6gpf toilet, it will usually underfill the bowl and so you won't start with enough water in the bowl to make it flush properly. (In a pre 1994 toilet, 20% will usually overfill the bowl a bit.) The MP version lets you set it to precisely refill the bowl. (The original Toto GMax flush used a fixed 40% refill ratio, hence the 528T "Fits Toto" flavor of the valve, which was standard equipment on most Totos for years. Now, you just get a 528MP for less money and open it all the way on a GMax; you roll it back to about 28% on the Toto EMax and other 1.28gpf toilets, which use 1 gal to actually flush and .28 gals to refill the bowl.)
 

WJcandee

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I installed the Cimarron for someone else and they want to stick with the Kholer parts...

So CUTE!!! They think that there is such a thing as "Kohler" parts! They don't understand that Kohler just buys these parts from the lowest bidder (and then marks them up for replacement).

They think that if they called any plumber in the United States they would get "Kohler" parts. Sweet, isn't it?

Any plumber would just rip out what is there, put in what he wanted (usually a generic or "Pro" 400A or 528) and tell them that that was the replacement Kohler part. Done.

Just like any plumber is going to install anything other than the (cheapest) black Korky flapper on a generic 2" flush valve. (rolleyes)

They install the stuff that they know works because they don't want to come back. And they don't want to pay any more than they need to for it.

I wish your friend luck with his/her "Kohler" parts!! :)
 

itsr-ent

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Kohler is sending a replacement. With the holiday, etc. I didn't feel like waiting, so I put in a 400A. This one works! (for now). The Kohler Fluidmaster 400 had some little purple adapter stuck into the overflow port, but it transferred over fine. Seems like a flow limiter, as it significantly reduced the overflow tube output.
 

Terry

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Kohler is sending a replacement. With the holiday, etc. I didn't feel like waiting, so I put in a 400A. This one works! (for now). The Kohler Fluidmaster 400 had some little purple adapter stuck into the overflow port, but it transferred over fine. Seems like a flow limiter, as it significantly reduced the overflow tube output.

That prevents overfilling the bowl.
 

hj

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quote; This is the third one I've installed, and the 3rd one I've had issues with!

Then you must be the unluckiest person on Earth, since I have used THOUSANDS of them in the past 40 years without that kind of problem.
 
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