Fluidmaster toilet fill valve. Change seal or whole valve

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i have a few old fluid master toilet fill valves laying around . So it seems its the top seal that goes bad in them and it can be replaced in 30 seconds . i saw a kit on amazon 10 for $15 .

Anyone ever just change the top diapram on one?

 
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Sorry, finally got the video to load and seen you were referencing a different seal than I was talking about. You can disregard my post. Sorry about that.

I change my seals out every 6 months or so on our 2 toilets. I get the 2 pack on Amazon for about $9. It’s very easy and quick to swap them out. They get little air bubbles in them and don’t form a good seal and you get “ghost flushes”
 
The seal is what usually goes bad and can be accessed by popping off the black cover. I have done it a couple times. It's easy and quick.
 
I just do the full rebuild, new everything becuase the fluidmaster kits are so cheap online. Did it on the 3 toilets when we moved in.

Not sure why you would need to replace this every 6 months. Should be more like every 6 year or more.
 
Yes, I have just replaced the top diaphragm. I once got the whistling sound mentioned at the beginning of the vid. It was weird because it would come and go and happen out the blue. For a while I wasn't sure where it was coming from. I wouldn't buy 10 of them though because in my experience they last a very long time.
 
Thanks for posting this! Today one of my project is to replace the valve in a toilet we have that is always squeaking. I may try this seal route instead, although the valve assembly is more than 11 years old and since I already have the replacement valve may be best just to replace it all?
 
Very Interesting. I always wondered what went wrong inside the valves so that they got so slow and started having ghost flushes during the night. I've never seen just the diaphragm in the stores. The complete assembly is only about $10 however.
 
most the time you can flush the valve out by removing that diaphragm turning the water supply back on with a cup over the valve.. use your finger or old soft tooth brush to clean sediment/debris from diaphragm. when I worked apartment maintenance I replaced dozens of those valves by the time those diaphragms were shot the valve was due to be replaced also.. I would replace the entire assembly
 
Very Interesting. I always wondered what went wrong inside the valves so that they got so slow and started having ghost flushes during the night. I've never seen just the diaphragm in the stores. The complete assembly is only about $10 however.
https://www.amazon.com/Danco-80141-Diaphragm-Fluidmaster-Ballcocks/dp/B00JJXJ5AU

fluidmaster also has their own packaged and branded. I may have seen them at Lowes usually something more commonly found at those mom and pops hardware stores.
 
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I would not waste a customers time, or my own by rebuilding a fill valve of this type. They are too easy to change out with new. I suggest: Korky Pro, they work on all modern models and have been very reliable.

Fluidmaster is fine, but they also have a lot of issues.

1 out of 10 Kohler toilets, right out of the box, with a yellow colored cap on the fill valve, was stuck in the closed position, made by fluidmaster.

"Slow fill" unless it takes forever to fill, or the noise from the slow fill condition is unbearable, I would not change the unit until it did not turn off the water supply.
 
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"Slow fill" unless it takes forever to fill, or the noise from the slow fill condition is unbearable, I would not change the unit until it did not turn off the water supply.
I have never had one of the diaphragm valves fail to shut off. The fill time just gets longer and longer and there are, ahem, "occasions" when a 5 minute cycle time on flushes is inadequate.
 
I would not waste a customers time, or my own by rebuilding a fill valve of this type. They are too easy to change out with new. I suggest: Korky Pro, they work on all modern models and have been very reliable.
Plus, what if it's something else wrong with the flush valve ? Same thing applies for a homeowner, though in that case, if the new seal didn't solve it, I'd pull it back out and save it for the future.
 
I have never had one of the diaphragm valves fail to shut off. The fill time just gets longer and longer and there are, ahem, "occasions" when a 5 minute cycle time on flushes is inadequate.
Well, it happens quite a bit. The number 1 plumbing repair of the service industry is a toilet fill valve \ flapper failure. Normally, in the past if I got called for this condition, I would first verify either or, then replace both....... do you agree @walterjay
 
again many may agree or disagree but if you're near a plumbing supply house even if its worth paying a few extra bucks supply house parts are better quality. I used to get these from a local supply house
https://www.amazon.com/BrassCraft-Mfg-BCT015-Operated-Plastic/dp/B000BO9HP4 or https://www.plumbmaster.com/wolveri...astic-hush-ballcock-with-brass-shank/p/57728B

The Fluidmaster 242 seal is a standard part and there’s zero difference between what a plumbing supply store gets. But Fluidmaster does have brass shank parts for those who don’t trust plastic. I haven’t had a problem, but I use Fluidmaster Quick-Connect connectors that don’t overtighten with a mechanism that “breaks” when it reaches the correct torque.

https://www.fluidmaster.com/products/toilet/toilet-fill-valves/242-toilet-replacement-seal/0

I’ve bough one just in case, but haven’t used it. But I have taken apart a Fluidmaster 400A and found the seal was fine other than maybe a little bit of sand or rocks that needed to be cleaned out. Or the seal might need to be cleaned off because of some sort of film buildup. They will need to be replaced if the seal has a tear.
 
I know it’s not the OP’s video. However, any kind of hard water situation like that thumbnail, and I’d just replace the whole fill valve every few years. I would save the little restrictor though for the fill tube if it was an OEM valve that comes with the toilet. Fluidmaster has a variety of performance versions of the 400A that come with fill valve restrictors. One version is a pinch mechanism that pinches the hose, while the other version uses a dial that controls the flow through a valve.
 
Bad seals cause a wide range of noises and symptoms that you wouldn't normally blame on a seal. And when you pull them off, they are still flexible and appear in perfect condition. But a new one fixes the problem and lasts for years.

If the new seal changes fix or changes the problem, don't save the old one "just in case". You'll put it back on the next time, thinking it's a new part because it looks in such good condition.

If you plan ahead (rarely an option for this part), you can get a good price on seals. The last three I've bought were under $2 each on Amazon, branded parts sealed on individual retail cards. But the price is often higher, typically exactly matching the Big Box store. If I was faced with paying $6, I would opt to try the ProPlus 10 pack from Home Depot for $6.52 or the least expensive complete assembly at $8-9.
 
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