What is the toilet fill tube?
The toilet fill tube is an integral part of the toilet tank responsible for controlling water flow into the toilet tank. The fill tube is situated beside the overflow tube, and both of them combinedly can make the flushing and overflow of water in a balanced ratio. You may face a lot of trouble if the toilet fill tube keeps popping off, a frequent problem that can be a part of daily life.
Bonus: How to remove a stuck toilet fill valve nut?
The working mechanism of the toilet fills tube:
The refill tube is heavily attached to the float rod adjustment screw and with the peripherals of this device, the trip lever, and an overflow tube. When you turn on the valve of the water supply, then water enters the refill tube and fills the tank. There is a close and consecutive linkage between the refill and overflow tubes. If water seems to be inundating the toilet tank, the overflow tube controls water flow, and the refill tube is immensely linked to this process. That’s how a toilet fills tube works, and there are several causes of popping out the toilet fill valve, which are going to be discussed in the following phases.
Why Does Toilet Fill Tube Pop-Out?
If you have a bathroom adorned with lots of fixtures and devices, then you are most probably acquainted with the dire screams of these devices. If you are using Kohler or Toto toilets, there are lots of causes of popping out the fill tube from its actual position. Some of those causes are discussed in a brief manner.
The bottom seal is worn out:
The bottom seal works as the perfect supporting agent for the fill tube, and nothing fancy. If the bottom seal catches unwanted dust and mist, then it becomes more rigid and lists its actual flexibility. Then pushing the handle off, the toilet becomes more difficult, resulting in the popping off the fill tube. So, when finally getting to release the portion, the handle goes too high and knocks off the tube completely.
Damaged Metal Clip:
A supporting piece of the metal clip keeps the fill tube in an ever-increasing position and works as the piston system for a fill tube. This metal ring is attached to the canister. If you only insert the tube down in the plastic tube, which has a larger diameter, it agitates the fill tube and eventually pops in and out.
Defected supporting rod:
The supporting rod, or, in other words, the trip lever, is raised when you flush the handle of the toilet. When the tube is too short, raising the handle can knock it off, and it will pop out. If the fill tube is of a shorter size, then it tends to be in the position that it clashes with the trip lever. This short time clash lashes out the fill tube from its actual position.
Damaged fill tube:
The most common cause of having a popped-up fill valve is the fill valve itself. A stiffening fill valve gambles with maintaining its actual position when it ages. Everything in this world has an expiry date, and the fill valve is not an exception. It lasts its actual efficiency if it crosses the red mark of age. Then it would be the biggest draw if you replaced the fill tube to make it more flexible and prevent unnecessary popping out. 
The overflow tube is not supported:
You may have probably known that the Overflow tube has always been a best friend for the fill tube as they juxtapose together; the fanciest thing is that a defect in the Overflow tube can also affect the fill tube. So do not forget to check the Overflow tube if you witness a popping-out fill valve.
How to solve the refill tube popping out problem in Kohler and Toto toilets?
There are tons of ways of solving the fill tube from popping out, and not all of them actually work. A lot of time could be wasted if you tend to go for each of the processes, and so here I will provide some of the most efficient ways of solving the pooping out the problem of the fill tube,
Use Zip Ties:
If neither of the methods works, we introduce Zip Ties to prevent excessive pooping out of the fill valve. Arranging the Zip Ties is the first thing that you must emphasize. You need at least three Zip Ties to bend the different zones of the fill tube. Put a zip loosely around the canister receptacle neck. 
Now put the second zip neck into the necktie, and finally, the third Zip Tie is going to be placed around the rubber hose of the fill valve. Then loop around a rubber band on the hose for increased support. Keep in mind that all the Zip Ties must be connected with a connector zip; otherwise, they may lose their bonding, and the popping fill valve may reoccur.
Attach small clips:
The very first and most effective ways of fixing the fill valve are to Attach small clips to the fill valve. You may not find the metal clips with the product, so you need to order them from the nearest hardware shop. Join one of the sides with the overflow tube on the flush valve. You may be messed around in appointing the particular clip with its actual place. Always remember that the plastic clip will be applied at the black tower that is situated a few inches from the main fill valve. Then attach the metal clip hook with the plastic clip, and that’s it. It will eliminate the popping out of the fill valve.
Apply Powerful Cleaner:
The second most effective way of preventing the fill valve from popping out is to clean the fill valve. You can use non-abrasive toilet cleaning liquids like “Drano” to remove all the rot and dust out of the fill valve. Once it is cleaned decently, place it in its actual position. Check the placement of the fill valve. If it doesn’t work, then opt for the next steps.
Replace the Fill Valve:
If none of the actions is effective enough to stop the popping fill valve, then replacing it is the only solution. First, turn off the water valve and then flush the toilet so that no water is left in the tank. Then remove the lid and pull over the fill valve from its initial position. Unscrew all the nuts and bolts to do so. Now it is time to install a new fill valve. Then place the tube onto the open part of the overflow tube now. In other toilet systems, there’s a stop top port to connect the tube. After replacing the fill valve, turn on the water supply line and check if the fill valve can effectively fill the tank.
Hi, I am Jose S. Franz. Currently, I am working as a professional plumber, and our team offers various plumbing services at an affordable price. After my college education, I completed a vocational certification course in plumbing systems and worked with several construction companies. Since then, I have fixed lots of different toilet models, from older to the latest versions. So I have more than 22 years of experience installing plumbing systems and toilets in both residential and commercial buildings.
