Fluidmaster 242 Toilet Fill Valve Seal Replacement Part, Fits 400A Fill Valve , Black

I’m definitely not a plumber but I’m so proud to have fixed my ever-running toilet. Watched a quick YouTube video and poof it was done!

When in perfect and works perfect.

The float stopped working in our guest room toilet and the water kept running. We had a plumber in a year and a half ago to readjust the float to stop the water from running. He replaced the entire unit with the Fluid Master assembly. This bathroom doesn’t get much use because we don’t get many guest; but I two months ago I started using it because it’s closer to my sewing room. I was frustrated having to lift the tank lid and tap the stopper arm so I decided I was going to fix this myself. I Googled, ‘Water Running in Toilet.’ I came across a YouTube video showing a guy holding up this small rubber valve stating this may be the reason the water wouldn’t stop running. The guy in the video said it could be a $3 valve that needed to be replaced. So, Amazon to the rescue. For less than $2 this little valve fixed the problem. All we had to do was pull off the red cap on the assembly (I’m not a plumber and don’t know the name), pull out the old valve and replace it with this bad-boy. It worked! This little rubber valve fixed a big problem. The water stops running when the tank is filled. No more lifting the tank lid to tap the top of the stopper arm.

Fixed my toilet, just remember to cut water off

Exactly as described!

July of 2024The upstairs master bathroom toilet valve was leaking, so I decided to buy a valve seal (about $2.00 on Amazon) and fix the fill valve.August of 2024The new seal did not solve the problem and I finally decided to just get a new fill valve. While mopping the water out of the toilet tank I discovered (!) that the shut off valve was not turning off all the way. (The tank always had a little more water in it after I had just mopped out all of it.)The shutoff valve installed up there was a Brasscraft Multi-Turn Angle Stop connected to PEX. I did not want to deal with removing the PEX crimp so I found out about the Brasscraft repair kit.Part number is BCSR01This was not available at Ace Hardware, but it was on the shelf at Home Depot (cost less than $3.00).After turning off the house water I was able to disassemble the shutoff valve and install the new parts. The smaller black seal/ring on the end of the stem was no longer shaped like an “O” because a portion of the rubber had come off; the shape was more like a “C”. Upon replacing the valve handle and turning on the water to the house the shutoff worked correctly.Next, I removed the old Fluidmaster fill valve and installed the (“improved”) Fluidmaster 400H. After all the fiddling and diddling was finished, I realized that I had a new valve seal in the old fill valve that was headed for the trash. And the new Fluidmaster valve takes the same seal as the old one, so I could keep that seal for future repair.I removed the black cap on the old fill valve and took out the one-month-old (#242) seal and a small crumb of rubber fell off. Eureka! That must have been why the replacement seal in the old valve did not solve the leak. I looked more closely and used needle-nosed pliers to remove another (larger) piece of rubber that had formerly been part of the Brasscraft valve seal from the inside of the fill valve where the stem portion of the #242 valve seal went.CONCLUSION:The old Fluidmaster valve would have probably worked okay with or without a new seal. But the pieces of rubber from the Brasscraft valve were the thing that needed to be addressed. A new Fluidmaster valve solved the problem, but I also had to deal with the faulty Brasscraft shutoff valve to complete the repair.

If you have a Fluidmaster fill valve and you have the one of the following issues, this will solve it:A) You flush the toilet and it doesn't refill immediately. This could be a few minutes to an hour or more. If you remove the toilet tank lid and tap the fill valve float arm, the water fills the tank.B) You flush the toilet and it refills constantly or longer than it should. If you remove the toilet tank lid and tap the fill valve float arm, the water stops running.Both of these issues are caused by a worn out seal. You could replace the fill valve, but I've found this unnecessary. No need to spend the time or extra money.To replace:1) Shut off the supply line to the toilet. This is located on the left side of the toilet as you face it below the toilet tank. Turn the knob fully clockwise.2) Verify water to toilet is off. Do this by pushing the toilet float arm down. If water begins running, check the shutoff valve. You may need to shut off water to the house otherwise. You can also flush the toilet and see if it fills especially if you don't care to submerge your hands in water for the next step.3) Hold the fill valve by the stem with one hand so it does not spin. Use your other hand to gently but firmly press the top of the fill valve down and turn it clockwise slightly until the cap comes off. You can let go of everything at this point.4) The seal is usually in the cap, but sometimes may be on the stem. Note its orientation and pull it off. Replace with new seal in same orientation.5) Hold fill valve stem in one hand so it does not spin. Use other hand to gently but firmly push cap back onto stem and turn counter-clockwise. This will take a little trial and error, but don't stress, you got this.6) Turn on the shut off valve by turning the knob counter-clockwise fully.7) Verify the toilet fills as expected. If water is spewing from the cap, turn the shut off valve off and repeat step 5. The cap isn't on correctly.If you hear water running constantly, gently lift the float arm as high as it will go without bending it. If you continue to hear water running or you hear the toilet tank refill intermittently throughout the day, your need to replace the flapper.