Toilets – How they work & DIY tips

We’re going to skip the usual history lesson on toilets filled with quirky trivia and discussions on who really invented it and get to how toilets work.

I’m assuming if you are reading this it isn’t for pleasure. So let’s just get to it.

How They Work

The design of the toilet is an exercise in simplicity.

A siphon, in easiest terms, is water being pulled above it’s natural resting point by gravity.

The initial artificial or added energy drawing water through an opening continues to flow above it’s resting point due to the weight of the already Toilets, Blue Springs Plumber, How a toilet worksmoving water.

Now what’s this got to do with a toilet?

Well, if you dump a bunch of water in a toilet bowl it will overflow into the trap.

After that flow is started, the weight of the water falling will draw the rest of the water until air is introduced to stop the siphoning action.

It’s kind of like pulling a coiled rope through a tall looped pipe. The weight of the water is you at the bottom pulling the rope.

When air is introduced at the other end it’s like cutting the rope with scissors at that end.

The rest is pulled through but no more. That is the basic toilet flush cycle.

You could flush a toilet with a 2 gallon bucket of water. The tank is just stored watered waiting to be dumped into the bowl at a given rate to start the flush cycle.

Plumbing is simple and so are plumbers. That’s just how it is.



Toilets are physics at it’s most basic. Looking at the picture below you can see a toilet bowl.

The toilet bowl has a trap, A trap is just a way to prevent sewer gas from entering your home by trapping it behind water.How do toilets work

It’s also where clogs occur. Imagine dumping a bucket of water into the following image.

All that water would be forced down the drain by gravity.

Once it starts flowing fast enough, the weight of the water flowing down the drain will pull the rest of the water in the bowl down

until it sucks air and breaks the siphoning action. That’s the sucking noise at the end of the flush.


What About The Toilets Tank?

Remember, the tank is just water waiting to be dumped into the bowl to start the flush cycle.

In physics this is called “Stored Energy”. But knowing that isn’t going to get your toilet repairscrapper working is it? So let’s stay on point.

The toilets tank consists of a water supply, fill valve, flush valve and trip lever.

All of these things are there to prevent you from needing to keep a bucket of water next to the toilet.

They’re also the parts that my plumbing customers tend to rig with rusty paperclips and wire.

You know who you are.


Toilets Tank Components

Your toilets components will not all look the same. They will all basically work the same.

Manufacturers are redesigning these things all time. Sometimes to be compliant with changing federal regulations.

Sometimes because they want you to have to buy parts only from them.

If they reinvent the mouse trap and say its better than all the rest they can charge more for replacement parts.

When the patent rights run out they suddenly find a better way.


Toilets Water Supply

Toilets water supply, Toilet repairs, Blue Springs PlumbersThis is a standard flexible toilet water supply. Yours may be flexible or rigid.

It can by braided stainless steel, braided plastic, chrome plated copper or just plastic.

It connects the water shut off to the toilet tank.

Plumbing Tips 

  1. Buy the flexible stainless steel. They won’t leak and easy to install.
  2. Be sure to tighten the compression nut attached to the stop valve completely. They sometimes feel tight when they aren’t.
  3. Don’t over tighten the nut attached to the bottom of the fill valve. That could cause the nut to split or the fill valve shank to crack.


Water Fill valve

Toilets fill valve, toilet repairs, blue springs plumberThis is a standard fill valve.

It’s function is to introduce a measured amount of water into to your toilets tank and flush valve. It usually does this with a float system.

Once the water gets to a set level a float with an arm attached will slowly force down on a button that shuts the flow of water off.

This works kind of like a see saw.

Yours may have a long rod with a ball float on it or even be a small flat device at the bottom of the tank.


Plumbing Tips

  1. This style fill valve is most common and easiest to install.
  2. For major water level adjustments pull up on the nut in the middle of the valve shaft. This will allow the flush valve to telescope up or down. Then push down on the nut to lock it back into place.
  3. For minor water level adjustments turn the vertical rod running paralell to the valve shaft. This will raise or lower the starting float position.


Flush Valve

Toilet repairs, toilet fill valveA flush valve has a few different components to it as well.

The tank water flows through it during the flush cycle. It is what the flapper is attached to.

It also has a small fill tube attached to the top that comes from the fill valve.

Water flows directly into the overflow part of the flush valve to refill and clean the toilet bowl.

The overflow tube is the top of the flush valve. This works as a fail safe if the fill valve doesn’t shut off and water continues to flow into the tank.

Plumbing Tips

  1. Be sure the top of the overflow tube of the flush valve is below the toilets handle. If the fill valve sticks on,  water could run out the handle opening.
  2. A common leak is a small burr or debris on the seat where the flapper seals against the flush valve. Lightly rub your finger along it to feel for any malformation. A fingernail or fine sandpaper is a good remedy.
  3. Sometimes the overflow tube isn’t glued well into the base of the flush valve. When looking for a leak shine a light down the overflow and check for leaks.


Trip Lever

Toilet repairs, Blue Springs PlumbingTrip levers or handles come in many shapes, sizes and materials.

When replacing yours try to keep with the same kind.

All they do is pull up on the flapper to allow the water to flow into the bowl thus starting the flush cycle.

Plumbing tips

  1. The mount nut is reverse threads.
  2. Leave the mount nut loose. If tightened it could shift and hold the flapper up.
  3. Brass is the best.


Some Tips 

  • When using a friends bathroom always hold the handle down until the toilet completely flushes. This will prevent clogs.
  • If your toilet wobbles use pennies to shim it. They’re cheap and work better than plastic shims.
  • Leave just 2 or 3 links of slack in the flapper chain. You won’t have to hold the handle down to make it flush.
  • Trim excess chain off the flapper. It can get stuck under the flapper and cause leaks.
  • Older models not flushing well can sometimes be salvaged by cleaning calcium build up in the jet. The jet is a hole in the bowl that shoots water straight down the drain during the flush cycle. This assists the flush cycle on some toilets.
  • Most stains can be removed from porcelain with a pumice stone.
  • Prevent toilets from slipping on slick floor surfaces by caulking the base with 100% silicone. I prefer clear because it’s easier with which to work.
  • Let your plumber provide your new toilet. We know the best models. It’s worth the mark up.
  • Don’t put any cleaners of any kind in the tank. It will compromise the rubber seals and cause damage. Use disinfectants and cakes that mount in the bowl.



There are many different options for toilets that can improve your quality of life.

When purchasing a new one I always recommend a high efficiency model.

They are pretty economical now and perform so much better.

Compare the difference in price between a standard and high efficiency model with the cost of one plumber visit.

I recently purchased an accessory for my elderly aunt. She was having trouble gettingToilet repairs, Toilet grab bars up from the toilet.

So I installed a hand rail that mounts to the toilet seat.

It’s made a tremendous difference to her life and no more falling down in the bathroom.

Another accessory that can help the elderly is a thicker seat.

It raises the seat a couple of inches and helps handicapped and elderly people to get up.

I recently had a customer with a very clever and curious toddler. He decided to hide most of his toys in their toilet.

It took a couple of hours to dig all of them out. It included pulling the toilet and turning it upside down in their front yard.

An inexpensive precaution would be to buy a seat lock.

There are a lot of different designs and it will definitely save you a lot of problems and money.

There are even seats that have heaters, lights and bidets built in.

It may seem silly to some but to others they’re real comforts.

Why Call Us

So next time you find yourself in need of a new toilet installation or just a repair call your local plumbing professionals at Advocate Master Plumbing.

We are your neighbors and Blue Springs Missouri plumbing professionals that have your best interest in mind.

Here’s a video I really like that may help:


Other Services Provided

You may think, after reading this post, that all we do is toilet repairs and installations.

I promise we’re a full service residential plumbing service company.

We’re also a locally owned and operated family plumbing contractor.

Some of the other service we provide are as follows:


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