Stained toilet bowl indicates a running toilet (C) Daniel FriedmanToilet Repair Guide:
How to Diagnose & Repair Toilets

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Toilet Repair Guide:

How to diagnose and fix a toilet: this article series discusses the cause, diagnosis, and repair of toilet problems (water closet problems) such as a toilet that does not flush well, clogged toilets, slow-filling toilets, running toilets, loose wobbly toilets, and odors at leaky toilets. Here we explain how to diagnose and repair problems with toilets, leaks, flushes, odors, noises, running and wasted water.

Found here: How to diagnose & fix a slow-flushing toilet or a clogged toi8let drain. How to diagnose and fix a clogged toilet drain - How to fix a toilet that is overflowing when flushed - in an emergency.

How to diagnose and correct drain noises occurring when the toilet flushes & how to repair problems causing plumbing drain sounds. Slow toilet tank fill problems. Toilets that keep running - fill valve does not shut off the toilet tank fill valve? Toilet flush valve or flapper valve problems.

Toilet tank fill valves and water sanitation. Sewer gas odors in buildings traced to loose or leaky toilet drains.

Our page top photo shows ugly staining in a toilet bowl - strong evidence that this toilet has been running, wasting water, possibly flooding the septic system, and sometimes giving bad flush performance as well.

We also provide a MASTER INDEX to this topic, or you can try the page top or bottom SEARCH BOX as a quick way to find information you need.

List of Toilet Fill, Flush, Drain, Odor, Noise, Problems & Solutions

Plumbing drains (C) Carson Dunlop Associates

If your toilet is overflowing or about-to see TOILET OVERFLOW EMERGENCY

All modern toilets receive human waste, urine, feces, and are intended to dispose of that matter in a sanitary fashion.

By the late 1800's the development of the modern flush-toilet, replacing chamber pots and outhouses, toilets have relied on a dose of water to flush waste out of the toilet bowl into sewage piping or into a private septic system for wastewater treatment and disposal.

Some sources refer to a toilet as a water closet. Thomas Crapper & Co. (London) called their scary-looking toilet contraption an "Elastic Valve Closet".

Early flush toilets like this 1890 model used a high wall-mounted reservoir tank, typically wooden, to provide adequate pressure and flow rate to clean and empty the toilet bowl.

Contemporary toilets use a tank attached to the toilet bowl itself, relying on improved flush valve controls to provide the water flow rate into the bowl to empty it and clean the bowl sides.

We discuss onsite waste disposal systems - septic tanks, drainfields, separately at SEPTIC SYSTEM INSPECT DIAGNOSE REPAIR

Toilet with tank lid on seat(C) Daniel Friedman

Before launching into our series of articles on diagnosing and repairing toilet problems such as clogged toilets, toilets that don't flush properly, running or leaky or noisy toilets, toilet odors, and loose toilets, take a look at the simple connection between a typical reservoir-tank toilet and the soil stack (waste piping) in the Carson Dunlop Associates sketch (above left).

At page top or left please see our list of toilet trouble diagnosis and repair articles.

You will see that some toilet problems are fixed easily and right at the toilet by a simple adjustment, while others may not be the toilet's fault at all, and may need more thoughtful diagnosis and repair.

Taking off the toilet tank top: Some of these simple toilet diagnosis steps require that you look into the toilet flush tank on the back of the toilet.

Just lift the top off of the toilet tank and set it carefully aside on the floor where you won't break it or trip over it.

If you leave the tank top on the toilet seat (as we did for this photo) you're asking for trouble, and also, it's a bit in the way.

Our sketch below shows the parts you'll see inside the toilet tank. You may want to refer back to this drawing while reading the details of each class if individual toilet problems listed above and how they are detected, diagnosed, and repaired.

Toilet tank parts (C) DanieL Friedman

Tank reservoir toilets like the toilet in the sketch at left and in our photo just below, have been in wide use in North America since the 1940's.

While there have been improvements in toilet tank fill valves, flush valves, floats, and water savings, the design has remained about the same.

A flush lever moves an arm to lift a flapper valve or tank ball to permit water to rush into the toilet bowl below, washing away waste into the sewer pipe.

At the end of the flush cycle, a float arm, or a float moving on a vertical stalk (newer valves) drops to open a valve permitting the toilet tank to refill with water.

When the toilet tank water level reaches the proper level, the float closes the toilet tank fill valve.

Toilet Won't Flush at All - Tank Water, Disconnected Flush Controls?

If the toilet won't flush at all, what happened when you pushed the flush lever ?

Closing the toilet fill valve Toilet flush valve being pushed shut

Toilet Flushes Slowly or Backs Up - Clogged Toilet or Sewer Drain?

Chase Patrick Gilligan as a toddler- leads to Sewer drain clogged with childs underpants (C) Daniel Friedman

Is the sewer line or soil stack clogged? Our grandson Chase Patrick Gilligan, learning toilet training, flushed his peed-in underpants down the toilet.

We have also found child's toys, and once, a dog's bone clogging the waste line just below the toilet.

If other building drains are working fine, but one toilet is flushing poorly, it is possible that there is a local blockage close to the toilet itself.

Brian found this drain clog by asking Chase what happened to the missing underpants.

He then removed the toilet from the floor [image], and by luck, the underpants were able to be easily retrieved - unblocking the clogged toilet drain before a backup and toilet overflow catastrophe had occurred.

  1. See TOILET CLOGGED to diagnose and fix a blocked or clogged toilet
  2. See TOILET FLUSHES POORLY to diagnose and fix slow-flushing toilets caused by inadequate water volume in the toilet bowl or in the toilet tank or cistern, or caused by a partly-blocked drain, defective vent.
  3. For toilets (and urinals) that are operated by building water pressure alone and without a reservoir tank, see FLUSHOMETER VALVES for TOILETS URINALS.

Stains in Toilets

Toilet bowl algae or mold growth (C) Daniel Friedman

Question: pink or black algae in toilet bowl

My toilet bowls develop a pink and / or black algae (?) after only a week of non-use (or use, for that matter). Is there something I can safely add to the tank water (I have a septic system) to prevent this? Why does it happen? - Anon 6/7/12


Anon, indeed I occasionally find both mold growth and algal growth in toilet bowls, usually when a toilet has been left un-used for a time (not flushed often enough to wash contaminants down the drain).

Try cleaning the toilet bowl thorougly with any toilet cleaning product. While you're at it, if your water is supplied from a private well or cistern, you might have your drinking water tested for contaminants as well.

Also check to be sure that the toilet is not running constantly like the one shown in our photo just above.

Question: Disaster zone toilet guide - emergency toilet flushing procedure & alternatives - can I use lake water to flush toilets?

Post hurricane sandy question:

Can I use lake water to flush my toilets. We still have no power, heat or water in Stamford, Connecticut - S.D., Stamford CT 11/5/2012

Reply: Suggestions for emergency flush procedures for conventional toilets when heat, electricity, or water are not available

Here are some suggestions for & warnings about using lake water or other reasonably-clean water from other sources to flush toilets in an emergency. Details about various options for flushing toilets in a disaster zone or ways to come up with emergency toilets are

In short, yes. Rather than living with un-flushed toilets, you can use lake water, snow melt, rainwater collected at a downspout, etc. to flush conventional water type toilets (or urinals or bidets) in a building connected to a public sewer or private septic system.

Watch out: but be warned: if your septic system is itself flooded, tank and drainfields, then there is some risk of a sewage backupinto your building when you try flushing a toilet. If you are pretty sure your septic tank and fields are at least not under water, or that the public sewer is no longer under water and flooded, you can test the private or public sewer system to see if you can begin flushing toilets:

  1. Select water that is free of debris and is clean as you can (it does not have to be sanitary, clear lake water would be fine) - don't use water loaded with weeds or other trash to flush a toilet as you risk clogging the drain system.
  2. Test a lowest-floor sink or tub drainage first: try pouring a few gallons of clean lake water (no weeds etc) down a bath tub drain or sink drain on your lowest floor. If that drain doesn't back up and no water comes up in nearby drains (floor drains, sink, shower, tub), then
  3. Test a toilet on the lowest floor next: try flushing the lowest toilet in the building - you can fill the toilet tank to the fill line and then flush, or (messier) you can try pouring some water directly into the toilet bowl until it begins to flush. We chose a toilet on lowest floor to avoid the unpleasant surprise of flushing an upper floor toilet only to see the sewage boil up out of a lower floor toilet in the building.

Watch out: if you flush via the toilet tank and flush valve and the toilet starts to back up or overflow, quickly

Other emergency toilet options for use when your home or building have no power, water, etc. include some simple and easy expedient methods for holding feces, toilet paper, and if necessary, urine such as using a plastic bag lined bucket or just using a plastic bag alone.


Continue reading at TOILET CLOGGED or select a topic from closely-related articles below, or see our complete INDEX to RELATED ARTICLES below.

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Toilet Repair Articles

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