Replacing A Toilet
And Fixing The Low-Flow Toilet Blues
Bruce W. Maki,
I was asked to fix a toilet that was running constantly.
There are two valves in a typical toilet, so there are two main
reasons that a toilet runs constantly:
- The fill valve can leak and let water into the tank.
The excess water will drip down the overflow tube into the bowl.
With this problem you can typically hear the water just barely
trickling, but trickling almost continuously.
- The flush valve can leak and let water drain into the
bowl. When this happens the water level in the tank will drop,
and the fill valve will open periodically, filling the tank
This toilet had a leaky flush valve. I could tell right away
because the water level was an inch below the overflow tube (as it
should be), yet I could see ripples in the water in the bowl. The
water level in the tank would drop slowly, then the fill valve would
open for a few seconds and I could hear water running.
The Fix For A Constantly-Running Toilet:
|The first thing I did was shut off the water
supply to the toilet.
Then I flushed the toilet to get the water out of the tank.
I arrived at this house with only a minimal amount of tools, and
none of the lighting equipment I carry on major projects, so some of
these photos are rather dark or grainy.
In The Tank:
- 1. The Flush Lever. This lever is raised up when
the toilet is flushed.
- 2. The Flush Valve, or flapper valve.
|The flush valve is actuated by a chain that
hooks onto the flush lever. I removed this hook.
||Then I reached down inside the tank and lifted
the flapper valve off its mounting tabs. Many toilets use an
all-rubber flapper valve, which comes off quite easily. This
hard plastic flapper required more effort... in fact, I thought
that I might break something.
|I examined the underside of the flapper valve,
just for kicks. Whenever I make a repair I like to confirm what
It looked like the flapper might not have been seating
perfectly at one spot (red arrow).
||The flapper seals against the valve seat
(arrow). I checked this seat to make sure there was no buildup
of mineral deposits, which could cause this problem.
At this point I headed to the nearest hardware store to buy a
simple all-rubber flapper valve, which usually costs about $2 to $4.
Being a bit lazy, I decided instead to go to a local plumbing and
heating supply store. I figured it might cost a couple of bucks
more, but their store was closer.
The New And Improved Flapper Valve:
There can be some big advantages to buying supplies at the
locally-owned, professional-oriented stores.
As soon as I pulled the old flapper valve from my pocket
the man at the store knew exactly what type of toilet I was
fixing. He recognized the part as belonging to an early
Kohler low-flow toilet.
He showed me this new-and-improved flush valve that comes
with new Kohler toilets. Right away I realized something. I
asked if the Styrofoam float was adjustable. He nodded. He
explained that if the float was placed lower on the
chain, that the flapper would stay open longer, and
if the float was placed higher, the flapper would close even
As you may recall, the Environmental Protection Agency forced
some changes on the plumbing industry back in the early 1990's. In
an attempt to conserve our resources, the EPA now requires that all
toilets sold in the United States use only 1.6 gallons per flush
(GPF), instead of the previous standard of 3.5 gallons per flush.
To comply with this rule, many toilet manufacturers modified
their flush valves to close prematurely. Instead of the whole
tank of water surging into the bowl, less than half of the tank
would empty out. But that simple change has not worked well for many
toilets. Millions of Americans have been irritated by toilets that
don't flush on the first attempt. Having to flush 2 or 3 times to
clear the bowl is hardly a wise way to reduce water consumption.
A lot of Americans have been annoyed by the government's
high-handed approach to something that affects us so personally.
Many parts of the country do not face any shortages of water.
Besides, the biggest culprit in water waste is lawn sprinkling. If
you really want to save water, then don't pamper your lawn.
||It turns out there are some sneaky, low-down,
possibly illegal ways to make a low-flow toilet work
properly. With this type of flapper valve, the plastic retainer
clips can be removed and the float moved downhill to a lower
When the float is placed lower on the chain, it will hold
the flapper open longer, letting more water flow into
With most low-flow toilets, restoring the flow closer to
the original 3.5 gallons per flush seems to make them flush
better, which is logical since many 1.6 GPF toilets are just
3.5 GPF toilets with a slight modification.
||After the flapper valve was installed, I noticed
that the chain was too long. I was about to cut the chain
shorter with a pair of wire cutters...
|...when I noticed that the flush lever had a
little socket for this type of chain.
||So I just snapped the chain into the socket and
wrapped the excess chain around the lever so it would not get
caught on something.
|It's hard to see the action of moving water in a
photograph, but the float is holding the flapper open even
though the water is almost gone from the tank. With the original
part, the flapper closed when the water was about 4 inches
I recently installed a low-flow toilet made by Eljer that made me
stop and think. It looked like they had simply made a hole in an
otherwise ordinary hollow flapper valve, so some of the air would
escape when the flapper was raised. Then the flapper would lose its
buoyancy and fall back prematurely, covering the big opening that
lets water rush into the bowl.
It occurred to me that replacing this flapper with an ordinary
replacement flapper (which would not have any little vent hole)
would restore the toilet back to its original 3.5 gallon per flush
design. I also noticed that Home Depot sells a couple of different
toilet flapper valves that are adjustable, so the homeowner can try
different settings to get one that works best and still conserves
Oh, lookey here...
The new Kohler toilet that I
in my own home a couple of years ago uses the same foam float
as in this article. I noticed that I could also adjust the
float height as described earlier.
But this toilet (the model is called Portrait, and it's
pretty expensive, about $250) works fine with the float in
the original setting, so I'll leave it for now.
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