Northwest Renovation Magazine

A Home Improvement Magazine

In all the years that I’ve worked as a licensed contractor, the single-most frequently asked question by homeowners is about the dreaded toilet hiss. One day I asked a journeyman plumber friend what caused it and how to stop it.

The first thing I learned is that as simple a system as toilets are they are also notoriously finicky. It’s not unusual for a newly installed toilet or flushing mechanism to require some follow-up tweaking. I also learned that the loss of water related to these “little” leaking problems can result in a considerable amount of water waste.

The toilet has two separate containers-water tank and the bowl. Everything else in between is essentially related to the flushing system. Try pouring some food coloring into the tank (not the bowl) and watch if the coloring makes its way into the bowl water without flushing it. If it does, something is amiss, most likely the “stopper” aka “flapper” is not functioning correctly.

The stopper is the rubber part that lifts up when the flush handle is pushed down. This movement allows water to enter the bowl. Once sufficient water has left the tank and “flushed” into the bowl, the stopper drops to prevent additional water from entering the bowl. Jiggling a toilet handle to get the toilet to stop running sometimes works because the chain that connects the handle lever to the stopper may be too long and gets tangled. The flapper then does not cover the hole properly and so the water keeps running until the chain is untangled to allow the flapper to close securely.

Fixing the chain is easy. You need only a pair of pliers, if any tools at all. Simply unhook the chain from the flush lever, shorten it a couple links and reconnect it. Don’t shorten it too much because this can create another problem. If the chain is too short, it may be too short to allow the flapper to drop all the way closed, or (depending on the flushing mechanism) may not be long enough to allow the stopper to stay open long enough for the toilet to flush adequately.

The flapper is the most common element in your toilet’s flushing mechanism that will need replacement. If you need to replace your tank flapper, here’s what to do:

Turn the water all the way off at the angle valve located behind the toilet bowl. (Figure 1) After the valve is shut off, flush the toilet. This will allow the water from the tank to run out, but because the valve is shut off, no water will refill the tank.

Figure 1

Figure 2

Figure 3

Warning! Before you touch the flapper, put on some plastic gloves, or use a paper towel to handle it. If the stopper is old, it will be covered with a coating of rubber silt that works like a dye on your skin or on anything it may drip on after removing it. Pull up any carpets or toilet covers before you remove it to avoid staining.

Reach down inside the toilet tank and remove the stopper and with a pair of pliers disconnect the chain from the stopper. (Figure 2)

Wrap the stopper in a paper towel and take it to a hardware store to ensure you come home with the correct flapper. Toilet stoppers are all pretty much the same, but there are some subtle variations that can make a difference when replacing them.

When you get your new stopper home, simply install it the way the old one was, making sure it moves freely and sits squarely on the hole.

Reconnect the chain to the stopper and then turn the water back on at the angle valve. After the toilet tank has refilled and the water has stopped running completely, flush the toilet to test your handiwork.

Once the tank has refilled again, it should shut off promptly, and with any luck, that should be the end of your hissing problem.

If the refill hose is too long this will also cause the toilet to refill itself periodically. The refill hose is a 1/4″ diameter hose that runs from the upper part of flush mechanism to the top of the overflow tube. It is usually secured to the top of the overflow tube by either a metal clip or plastic bracket. This hose should not insert into the top of the overflow tube by any more than one inch.

Tools & Materials Pliers, scissors or knife.
Where to Purchase A Boy Electric & Plumbing
(503) 225-9009
(800) 691-7895 for nearest location
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Average Cost $1.99 – $7.69

When you purchase a new flush mechanism kit, this tube comes with the kit and is usually 2″ to 3″ longer than it needs to be. Sometimes when the new flush mechanism is installed, the person installing it doesn’t know what to do with the extra length, so he just stuffs the entire length of hose down inside the overflow tube. When this is done the toilet can siphon water back up the hose from the overflow tube causing the toilet to periodically refill itself just like with the leaky stopper. To fix the problem, simply pull the hose out of the overflow tube, and using either a knife or scissors, cut it back so it goes down the tube no more than 1″, then put the hose back where it was. (Figure 3)

For this procedure, you don’t need to turn the water off.

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