If you've tried a new flapper to fix your running toilet and it still runs don’t give up hope. Here's a fix that's sure to work.
By the DIY experts of The Family Handyman Magazine:September 2010
Follow the directions included with your flush seat repair kit to seal a new repair seat onto
the old, damaged seat.
If you hear your toilet refilling too
often, or if you hear the steady hiss of
running water, the flapper may be
leaking. The flapper (aka “flush valve
seal”) is the plug that falls against the
drain hole (flush valve drain seat) on
the bottom of the tank and holds water
in until the next time you flush. When
flappers or flush valve seats wear out,
water trickles out, causing the water
valve to open to refill the tank.
Usually the fix is simple. Remove the
old flapper and take it with you to the
hardware store or home center to find
a matching replacement.
Occasionally a new flapper doesn’t
solve the problem. If you’ve tried
replacing the flapper but the toilet
still runs, the flush valve seat is probably
rough or pitted. You can replace
the entire flush valve, but it’s a big job.
Here’s an easier fix. Look for a flapper
kit that contains a flush seat repair.
We show a Fluidmaster 555C kit ($7),
but others are available. The kit contains
a flapper and matching seat that
you adhere to the damaged seat with
the adhesive provided, as shown.
Start by closing the valve on the
water line to the toilet by turning it
clockwise. Then flush the toilet and
hold the flapper open to allow the
water to drain from the tank. Use a
sponge to mop out the water that
remains. Follow the included instructions
to install the new valve seat and
flapper. The Fluidmaster flapper we
show includes a plastic cup that
allows you to adjust the length of time
the flapper stays open. It’s for toilets
that use 3.5 gallons or less for a flush.
If your toilet uses more than this,
remove the timing cup. Install the
new flapper. Then adjust the length of
the chain so it’s just slightly slack
when the flapper is down. Turn on the
water and test the flush. You may
have to fiddle with the length of the
chain to get the flapper working correctly.
When you’re done, cut off the
excess chain to keep it from getting stuck under the flapper.
Take the old flapper with you to find a matching replacement.
Have the necessary tools for this DIY project lined up before you start—you’ll save time and frustration.
If you need to shorten the chain, you'll need side cutter pliers or a chain cutter.
Avoid last-minute shopping trips by having all your materials ready ahead of time. Here's a list.
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