Tip & How-To about Plumbing

How to install a new flush valve

  • Flush valves are held to the tank by one large jam nut on the bottom of the tank. Installing a new flush valve usually requires removing the toilet tank from the bowl, which can be rather complicated. However, wall-mounted tanks may not need to be removed.

  • If the toilet tank must be removed, turn the water off completely, flush the toilet and hold the trip lever down to evacuate most of the tank water. Use a sponge to remove the remaining water. Disconnect the tank's inlet fitting from the water supply. If the flexible riser tube is damaged, replace it.

  • Then, unscrew the two rubber-gasketed bolts flanking the flush valve. These bolts go through the tank and bowl flange, with nuts beneath. Use caution–forcing the bolts may cause you to break the tank, bowl or both. Use plenty of penetrating oil on the threads. If they still won't budge without force, try wrapping masking tape around a hacksaw blade and sawing with the teeth facing you, so the blade cuts on the "pull" stroke. The layer of masking tape will protect the bowl's glazed surface from saw scratches.

  • The tank should now lift away from the bowl. Lay it upside-down on a throw rug or newspaper padding to protect it, and unscrew the large nut holding the flush valve to the tank. Use channel-locking pliers plus penetrating oil and extreme care to avoid breakage. Clamp a well-padded locking plier/wrench around the flush valve to keep it from rotating inside the tank.

  • Install the new flush valve according to the directions. The rubber gasket goes on the inside of the tank to prevent leakage. The flat washer fits on the outside to prevent tank damage.

  • Use new brass tank hold-down bolts, which will remain workable. Tighten the bolts just enough to compress the tank's soft rubber gasket and keep it from leaking.

  • Install the water supply riser to the tank and turn on the water.

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mansfield 160 toilet diagram


The tank bolts do not get removed. The flush valve is mounted in a hole toward the rear of the tank. The nut under the tank is removed to allow removal of the flush valve from the inside of the tank. The replacement flush valve is inserted into the hole inside the tank and the nut is installed to fasten it in place

May 15, 2013 | Danco Flush Valve. Replacement Flush Valve...

1 Answer

My toilet only leaks when flushed. It seems to be coming from the connection at the tank. The tank is not cracked and a new hose from tank to shut off valve has been installed. The toilet is only 4 years old


If you have 2-part toilet, then tank is attached to bowl with 2 bolts.
Look inside tank and you can see bolts with rubber washers located on either side of flush valve.
The 2 bolts hold tank and bowl together and between tank and bowl is a washer called the spud washer.
So spud washer could be leaking ... or 2 bolts could be leaking.

1) If bolts are leaking, there is usually dripping all the time, and drips are visible on bottoms of bolts
If spud washer is leaking, then tank could leak only when tank is flushed.

2) First thing to try is tightening nuts on the 2 bolts. Nuts may be loose. Tighten nuts a few turns, and check if toilet still leaks.

3) To fix a spud washer, you usually need a new generic one from hardware store.
Newer tanks with 1.6 gallon flush have special sized spud washer.
geno_3245_105.jpgTank is upside down and spud washer is fit over flush valve

If you cannot find new spud washer, re-use old one and smear retorseal on it during re-assembly to make sure it seals. Rectoseal is good for many home plumbing repairs. More about that in a moment.
geno_3245_104.jpg

4) To take apart tank: Disconnect supply line to tank. Empty water out of tank. Remove nuts from bolts. Lift tank off. Wash out tank with hose. Make sure there is no sand or sediment left in bottom that might clog up flush holes located inside bowl after tank is re-assembled.

5) Remove old spud washer, and put new one on. Do a google-image search for 'spud washer' if you need more photos. New spud washer fits over flush valve. That's it. And then reassemble tank.
If you want to apply rectorseal to washer, put washer on as shown in photo above. Then smear-or-gawm rectorseal over area of washer that sits on bowl. Rectorseal will make sure there is no more leaking.

Nov 24, 2010 | Bemis 1200 Slow Elongated Toilet Seat,...

1 Answer

how do i flush the pipes out? (when i flush the toilet it will not re-fill water) one of the answers was to flush the pipes


If you have a supply shut off to fixture shut it off and disconnect supply line from inlet to toilet . If your supply line to toilet is a flexible line then bend it so that you can direct water to small container. Slowly turn valve on to see what flow rate is at that point. If flow rate is not good then I would shut water off to house and replace valve. If flow rate to toliet is good I would reccomend you replace flush vallve. To do this shut off water supply to toilet. Disconnect supply nut to bottom of flush valve. There will be a retaining nut that holds flush valve in place in toilet tank. Remove flush valve after removing fill tube from flush valve to overflow tube. Replace with toto replacement valve or use Fluidmaster 400A. Instructions on box of 400A are easy to follow and if you have flex connector you won't need supply line washer. I would reccomend that before you install new valve that you put rubber gasket on shank of valve and slid it about halfway up the shaft. Make sure that inside of tank is dry and use a small bead of silicon caulking on top and bottom side of shaft gasket. slid gasket the rest of the way on valve shank,install in tank and put on retaing nut hand tight. Push down on top of valve and using channel lock pliers finish tightening nut securely.You may need to reach into tank and grasp valve body to stop it from turning. There are other things you can do if you have a working supply valve. Shut off valve and remove screws that hold top of valve in place and remove and clean surfaces. You can turn valve on slowly to help flush out any rust or mineral deposits. I hope this is of some help to you. Thanks

Nov 21, 2010 | Toto Carlyle 1-piece Elongated Bowl Toilet

1 Answer

Jacuzzi sent me new rubber gasket for attaching flapper assembly to tank-(held in place with a large white plastic nut) Does the totally flat side of the rubber washer face the tank or away from the tank? Also, how tight should this connection be?


The rubber washer goes to the inside of the tank under the flush valve which gets screwed on with the large plastic nut on the bottom side of the tank. Then the foam gasket fits over the plastic nut which goes into the toilet bowl hole for the water to flow into the bowl. Tank needs to be removed from the toilet bowl.

Aug 31, 2010 | Jacuzzi Bath Era BK37 959 White toilet...

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