Replaced 2 Fluidmaster valves toilet still running

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shooter1951

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I have a Mansfield toilet in our spare bathroom I recently placed one of those chlorine hanging sanitizers. After I did so the toilet started running every 5-6 minutes. I thought I may have dislodged something with the flush valve so I replaced it with a Fluidmaster Universal type. After installation about every 2-3 minutes it runs for about 5 seconds. I figured the new valve was bad so I installed another one. Same thing. I consider myself above average handyman/diy guy, having built 2 new homes. This may be very simple but am I missing the obvious? Also I did remove the chlorine sanitizer before I put the second Fluidmaster on just in case the problem was related to it. Any suggestions are appreicated.
 
The mistake most DIY make is pushing the refill tube down inside the overflow tube. There is clip that fluid-master supplies with there fill that holds the refill tube above the overflow. When the end of the refill tube is below the water level in the tank it causes the tank to siphon water into the overflow. Use the clip if you still have it.
 
Just a add-on to what John has said ,besides the fill valve refill tube you should check the seal on the flush valve. Those seals get small water bubbles on the seal itself ( water gets in small holes on the top or bottom sides of the seal creating the bubbles) causing the seal to not seat flush allowing water to seek out the tank. I recommend removing the chlorine puck out the tank as well , the chlorine shorten the life of the tank inner parts.
 
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The mistake most DIY make is pushing the refill tube down inside the overflow tube. There is clip that fluid-master supplies with there fill that holds the refill tube above the overflow. When the end of the refill tube is below the water level in the tank it causes the tank to siphon water into the overflow. Use the clip if you still have it.

Thank you John. I read that on another post so I did go back and use the clip.
 
Just a add-on to what John has said ,besides the fill valve refill tube you should check the seal on the flush valve. Those seals get small water bubbles on the seal itself ( water gets in small holes on the top or bottom sides of the seal creating the bubbles) causing the seal to not seat flush allowing water to seek out the tank. I recommend removing the chlorine puck out the tank as well , the chlorine shorten the life of the tank inner parts.

Thank you for the post. As you suggested I believe the flush valve seal is the culprit. I did pick one up and just put it on this morning. The old one was deteriorated pretty bad I don't understand how it wasn't leaking worse by the looks of it. (Which by the way I also removed the chlorine attachment as I suspect that was the reason for most the deterioration). Now to my next problem/question: How do you get the new seal to seat? After taking the old one off and cleaning where it sits I installed the new one by pushing it all the way down over all the threads. When I tried flushing it is leaking worse now. I took it back off and tried just putting seal over top of the lip so it kind of rested "above" the threads. This worked better but it still leaks. I checked the bottom of the flush valve itself and it appears to be fine (no cracks, smooth on the bottom where it seals, etc). I took a straight screwdriver and ran around the bottom so it appears the seal sits flush and tried it a third time............same thing. Any ideas what I am doing wrong? I double checked and the seal is the correct one for Mansfield. Thanks again for any suggestions.
 
Did you remove the tower off the flush valve to install the new seal. Sounds like the seal is not installed properly. Photo #1 shows a break down of the flush valve( remove the top nut then remove the tower to install the seal properly on the flush valve). Photo #2 shows where the seal should be installed (between the red lines)

photo.JPG

photo 2.JPG
 
Did you remove the tower off the flush valve to install the new seal. Sounds like the seal is not installed properly. Photo #1 shows a break down of the flush valve( remove the top nut then remove the tower to install the seal properly on the flush valve). Photo #2 shows where the seal should be installed (between the red lines)

Yes thank you again for the reply IFIXH20, it is appreciated. I did remove the tower as the picture shows. From the side view of your picture with the red arrows is there a "track or channel" the seal sits in or is that the threads on the flush valve? I first tried pushing the seal all the way down past your red arrows so the new seal was close to the black gasket in your picture. After trying it there it the water kicked on about every 10-12 seconds. I then pulled the seal up near the top of the threads on the flush valve (about where your arrows are). The water kicked on about every 20 seconds or so. If I place the seal between the arrows it will have a "cone" shape with the outer edge of the seal dropping down correct? I will try it again in the morning. If it still leaks I will get a new flush valve and see if that fixes it. Thank you again for your help.
 
Yes there is a slot between the red lines for the seal . If the seal is installed correct the seal should be flat not coned. Are you sure you have the seal for the Mansfield because American Standard has one that looks just like it (same color).
 
Make sure its the original mansfield and not aftermarket. Aftermarket usually does not work.
 
Yes there is a slot between the red lines for the seal . If the seal is installed correct the seal should be flat not coned. Are you sure you have the seal for the Mansfield because American Standard has one that looks just like it (same color).

FINALLY fixed!! I checked the area with a flashlight to be sure there was any residue in the slot and there was a tiny piece of the old one still there. It was so small you couldn't see it inside the slot from above. I missed it the first time I ran the screwdriver around it. But it was not allowing the new one to set correctly. After reinstalling (correctly) I was able to spin the new one to make sure it was in all the way around. Thank you for all your suggestions and guidance. To make sure it was the correct seal. I picked the new seal up at Lowes and it said it was for Mansfield #210. I was starting to think maybe mine was a different model but this seal was right next to the Mansfield flush valve that looks like mine. Thanks again to everyone's help. :):)
 

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