Repairing a Leaky Toilet Tank Flush Valve

Toilet valve repair
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  • 01 of 10

    Leaky Toilet Tank Flush Valve

    fluidmastter flush valve
    Fluidmaster 555C Retrofit Kit "Flusher Fixer". © 2007

    One of the most common and most frustrating toilet tank problems is the slow leaking of tank water through the flush valve, into the toilet. As the water leaks, the tank water level falls and the toilet ballcock fills it back up again. It's a wasteful and annoying problem.

    Well, one of the neatest products I've found is a sub $10 repair kit made by Fluidmaster called the Fluidmaster "Flusher Fixer" Model 555C. It allows you to repair the flush valve with a fool-proof valve kit...MORE that anyone can install. In this tutorial, I'll show you how easy it is to install and you can save over $100 in a Plumber service call.

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  • 02 of 10

    Turn Off the Water Supply

    toilet water supply shut off valve
    Turn Off the Water to the Toilet Tank. © 2007

    The first step in the toilet repair is to turn off the water supply to the tank. If you do not have a localized shut off valve, you need to shut off the water supply at the water meter.

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  • 03 of 10

    Remove Old Drain Valve Flapper or Ball Assembly

    old flapper flush valve
    Remove the Old Flush Valve Assembly. © 2007

    Once the water supply is turned off, flush the toilet to drain the tank of most of the water.

    Remove the old tank ball or flapper ball along with any guide wires or flush lever chain. You want nothing left of the drain valve assembly. You want just the drain valve seat to be exposed.

    Be careful not to drop anything into the drain valve opening or you could cause a clog.

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  • 04 of 10

    Remove Excess Tank Water

    drain water from toilet tank
    A Wallpapering Sponge Works Well to Absorb Remaining Water But Any Sponge Will Do. © 2007

    Once the tank is drained and the old valve ball is removed, there will still be water left in the very bottom of the tank between the tank bottom and the top of the flush valve seat. This water needs to be removed and the easiest way to do this is to use a sponge. I've found a wallpaper sponge works pretty well. If you don't have one handy any sponge will do.

    Sop up the water, squeeze it out into the sink and repeat until the tank is fully drained.

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  • 05 of 10

    Clean the Valve Seat

    cleaning flush valve seat
    Proper Valve Seat Preparation is Essential for a Good Seal. © 2007

    If the old drain valve seat is brass (most are) it needs to be cleaned. The easiest way is to use steel wool or fine sandpaper and clean the seat of any residual debris.

    Rinse it off with a soft cloth and then dry it fully with a towel or hair dryer. If you use a hair dryer be sure not to heat just one spot for a long time.

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  • 06 of 10

    Install Sealant Ring Onto Drain Valve Seat

    preparation for new flush valve
    The Adhesive Sealant is the Secret to This Easy Repair Kit. © 2007

    The slickest part of this retrofit system by Fluidmaster is the sealant ring they provide. Just peel and stick!

    Well, OK, not quite that easy but almost. Just peel the paper from one side, then carefully center it over the opening of the cleaned valve seat. Press lightly to set it in place. Do not press too hard!

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  • 07 of 10

    Flapper Ball Assembly Detail

    flapper ball
    Flapper Ball Seat Ridges. © 2007

    In this picture, you can see the ridges under the flapper ball valve seat that will be pressed into the sealant putty. This will create a strong watertight seal.

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  • 08 of 10

    Position the Flapper Ball Valve Assembly

    replacement flush valve
    Simply Position the Valve Assembly So It Can Open Unobstructed. © 2007

    Before you remove the paper on the sealant ring, test fit the best location of the flapper ball valve assembly.

    • Try to position at about a 45° angle so that the tank ball can freely pivot and open fully when lifted by the chain.
    • The chain should pull straight up or angled slightly back toward the hinge of the tank ball.
    • Once you have the proper location, remove the paper from the sealant ring.
    • Place the flapper ball valve assembly over the sealant ring in the proper position and press down firmly to...MORE seat the bottom into the sealant ring.
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  • 09 of 10

    Attach Lift Chain

    chain attached to flush valve
    Attach Chain So There Is a Slight Amount of Slack. © 2007

    With the new valve assembly firmly seated in position, the next step is to attach the lift chain:

    • Make sure the tank ball is closed.
    • Make sure the toilet flush lever is down.
    • Connect the chain attachment clip to the hole in the flush lever.
    • Connect the clip to the proper plastic chain link so as to provide a slight slack in the chain.
    • Trim unneeded chain links leaving a few extra hanging from the attachment clip.
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  • 10 of 10

    Turn on Water Supply and Fill Tank

    fill valve
    You're Done! Now Just Fill The Tank. © 2007

    All that's left is to turn the water supply back on, let the tank fill up and check the flush operation. If you need to adjust the chain length to achieve proper operation do it now. Once the flapper ball lifts up and the fill cup tilts back to fill with water, the valve is operating properly.

    You're done! This problem won't bother you again for a while and you just saved over $100 in repair bills.