Toilet Flush Valve Replacement

Toilet handle
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  • 01 of 08

    Toilet Flush Valve Replacement

    Toilet flush valve
    Aaron Stickley

    A toilet flush valve replacement may be necessary when replacing the flapper if other attempts to repair a running toilet don’t work. If a toilet flapper that is is good shape doesn’t seem to seal, it's likely that a toilet flush valve replacement may be the solution. Although it's more difficult than most toilet repairs, the average handy homeowner can manage a toilet flush valve replacement and prevent the need to buy a new toilet.

    Begin by shutting off the water to the toilet; put a bowl under the water line to catch any residual water. Then, remove the water line from the toilet. If the valve under the toilet does not shut off all the way, you can turn off the water at the main.

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  • 02 of 08

    Remove the Toilet Tank

    Old toilet tank bolts
    Aaron Stickley

    Remove the nuts that hold the tank onto the bowl of the toilet. Most of the time, these are wing nuts and you can simply remove them by hand. If not, give them encouragement with pliers. In the worst case—if the nuts will not come off—cut them off with a hacksaw type blade that can fit in between the tank and the bowl. After the mounting nuts are removed, carefully pull the tank off and put it somewhere safe where you can work on it.

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  • 03 of 08

    Remove the Bolts

    Rusted toilet bolts
    Aaron Stickley

    The mounting bolts may have a second set of nuts holding them onto the toilet tank. Remove them by unscrewing the nuts, if possible. In the case of older toilets, the insides may be so rusted that the only way to remove the bolts is to cut them off; you can accomplish this with a hacksaw or mini hacksaw.

    It’s fine to cut through the rubber washer and into the bolt. You may not need to change the bolts, but in most cases, it’s better to use new bolts.

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  • 04 of 08

    Remove the Old Flush Valve

    Remove flush valve
    Aaron Stickley

    With the bolts out of the way, it's very easy to get to the flush valve nut and remove it with large pliers. Once the main flush valve nut is loose, pull the flush valve out from the top of the tank. Clean up the toilet tank before installing the new hardware.

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  • 05 of 08

    Install the New Flush Valve

    Toilet flush valve
    Aaron Stickley

    An adjustable flush valve is a good option because it can be set to whatever height is necessary; however, most universal flush valves with work with the majority of toilets. Make sure the big flush valve gasket goes on the inside of the toilet tank and the nut and washer on the outside.

    Follow the directions for the appropriate angle to mount the flush valve in the tank. Tighten the flush valve nut hand tight and then an extra 1/4 turn or so with pliers to make sure it’s tight. Fit the tank to bowl gasket over the flush valve on the bottom of the tank.

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  • 06 of 08

    Install the Tank Bolts

    Toilet tank bolts
    Aaron Stickley

    If possible, use tank-to-bowl bolts with a washer inside the tank and a second on the bottom of the tank for each bolt so the porcelain is sandwiched by rubber washers. Tighten the nuts onto the bolts. Notice how the nuts look tight, but they are not compressing the rubber out much between the washer and porcelain. Beware, as it's possible to crack the porcelain if you overtighten the nuts.

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  • 07 of 08

    Set the Tank Onto the Bowl

    Replacement toilet tank bolts
    Aaron Stickley

    Make sure both bolts align right between the holes in the bowl and set the tank onto the toilet bowl. Install the last washer and the wing nuts. Tighten both wing nuts down by hand evenly, a little at a time. If you aren't sure how tight to go, let the tank fill with water, and the weight will help push the tank down; then you can tighten the nuts.

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  • 08 of 08

    Connect the Water Supply

    Toilet water supply
    Aaron Stickley

    Replace the flex line if needed or just hook up the old one if it’s in good shape. Turn on the water to the toilet. Now, adjust the flapper chain onto the toilet handle.

    Make any adjustments to the flush valve height if necessary so that the water level is at the recommended line and the overflow is 1 inch above that. Most importantly, check for leaks by flushing the toilet several times.