How to Replace the Guts of a Toilet

As your toilet’s innards—the flash valve, overflow tube, fill valve, etc.—have been dealing with gallons of water every day for years, it is possible that they have become rusty, with their rubber and plastic components deteriorating or even breaking. Instead of replacing your entire toilet unit, you can just replace its guts. Here are the steps to follow:

  • Secure the things that you will need for the project, including an adjustable wrench, pipe wrench, flat-blade screwdriver, scissors, tank-to-bowl gasket, tank bolt gaskets, fill valve gasket, overflow tube and flush valve, fill valve, tank bolts, refill tube and towels.
  • Turn of the water supply valve beneath the tank. Remove the tank lid and make sure you place it on a towel to prevent damage. Drain the tank, and if the handle does not work, lift the flap with your hand. Get rid of the remaining water in the tank by soaking it with a towel.
  • Using an adjustable wrench, rotate the nut that holds the supply line to the tank counterclockwise to remove it. Now, you should be able to access the fill-valve nut, so remove it by turning its nut counterclockwise and then you will be able to release the fill valve.
  • To stabilize the toilet bolts inside the tank, place a flat-blade screwdriver into their slot. Then, loosen the toilet bolt nuts beneath the bowl and the tank with an adjustable wrench.
  • Lift off the tank and lay it on a towel on the floor to access its bottom. Remove the rubber gaskets that surround the toilet bolts and then the nut that holds the flush valve using a pipe wrench. Grab the overflow tube connecting to the flush valve and then pull the tube and valve from the tank.

  • Place the gasket around the threads that come with the new flush valve and overflow tube. Most of the time, the flapper is already attached to the valve and tube, and if it is not, snap it over the plastic prongs located at the bottom of the overflow tube. Using a pipe wrench, screw the nuts coming with the flush valve to the threads found beneath the toilet tank. Then, cover the nuts and threads with the new tank-to-bowl gasket.
  • To start setting the tank on the bowl, thread the new gaskets onto the new tank bolts, which you should insert through the holes in the bowl and the tank. Tighten the nuts using an adjustable wrench.
  • Place the fill valve gasket over the end of the new fill valve and then insert the threads of the valve through the hole at the tank’s bottom. Screw the nut onto the fill valve and hand-tighten the nut to secure the valve in the tank. Attach the supply line back to the fill valve, tightening it with an adjustable wrench.
  • Slide the refill tube onto the fill valve connector and position the refill tube over the overflow tube. Cut the refill tube’s connection with scissors if it is too long.
  • Connect the chain from the flush handle to the flapper and replace the components in a reverse order of how you removed them. Turn the water supply back on to fill the tank with water. You should now be able to see the float stopping the water from flowing at the desired level. Return the tank lid back in place.

By following these steps, you will be able to replace the guts of your toilet.

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