How-To Replace A Toilet Fill Valve

If you own your home, or even if you rent, chances are high that you’ll need to perform some basic toilet repair at some point. Such as a toilet fill valve replacement. If your toilet isn’t flushing, if it’s very noisy, if it’s not filling correctly, or if it keeps trying to fill unsuccessfully, you might need to replace the toilet water valve. The fill valve is the part in the toilet tank that controls the flow of water into and out of the toilet bowl. It’s not hard to replace, but it might seem intimidating. Here is a step-by-step tutorial, with photos, on how to replace toilet fill valve to help you along the way.

Broken toilet water flush

DIY Level: Beginner

Materials Needed:

  • New toilet fill valve
  • Empty medium-sized bucket (an old ice cream gallon bucket works well)
  • Crescent wrench
  • Scissors
DIY Toilet Repair - materials

Every fill valve is different, although there are basic universal strategies to replace a toilet fill valve.

DIY Toilet Repair - turn water off

Step One: Turn off water

Turn off your toilet’s water supply, then flush the toilet. This will drain the tank so you access it.

DIY Toilet Repair- flushing system

Flushing the toilet with the water turned off will drain the bowl and tank without refilling it.

DIY Toilet Repair-bucket under

Place a bucket under the tank where the water supply hose connects.

Remove the water supply hose

Step Two: Remove hose

Remove the water supply hose from the toilet tank. If you pretend you’re lying on the floor looking upwards, you’ll turn it counter-clockwise.

Unscrew the mounting nut

Unscrew the mounting nut.

DIY Toilet Repair-remove all parts

Step Three: Remove all parts

In fact, you’ll need to remove all parts of the mount, including the o-ring if applicable. This may require a crescent wrench. This will also be a counter-clockwise turn, from the vantage point of looking upward from the floor.

mounting nut and washer

The mounting nut and washer.

Rubber o-ring

The rubber o-ring.

remove the old valve from toilet

Step Four: Remove old valve

With the mounting nut removed, it will now be simple to remove the old valve from the tank. So do that.

DIY Toilet Repair-remove valve
DIY Toilet Repair-water bucket

Keep the bucket in place, as removing the old fill valve mechanism will release all the extra water that didn’t empty from the original flushing.

DIY Toilet Repair-toilet tank

At this point, you’ll have an open hole at the bottom of your toilet tank from the old fill valve.

DIY Toilet Repair-fill valve model

Step Five: Prep the new valve

Depending on your fill valve model, your instructions may vary slightly from this tutorial at this point. But for this model of fill valve, it’s time to attach the tube to the valve opening. Push it on there tightly, making sure it’s sealed all around.

Water fill

Step Five: Set water depth

Now is time to set the water fill depth on your new valve. Spin the top of the valve counter-clockwise (looking down at it) to unlock it from the base pipe, then pull upward until it’s fully extended.

Toilet tank and new valve

While it’s in its fully extended position, set the valve in the tank as though you’re going to install it fully. (You’re not, at least not yet.) Press down on the top of the valve until the corner of the valve’s top cover lines up with your toilet’s fill line, or water fill, or flush valve line.

Line up valve corner

When the two (the valve corner and the water line) are lined up, take out the new valve from the tank. Keeping the new height stable, twist the valve’s top clockwise to lock it into place. You’ll hear a click, or a snap. Keep the valve locked from this point on. After locking it, put the valve back into tank so that the tube points directly at (or above) the flush valve. Double-check to make sure the corner and water line still line up.

mounting nut under the tank

Step Six: Install nut

Install the mounting nut under the tank, which will hold the new valve in place. Make sure the beveled side of the mounting nut faces upward.

avoid cranking down with a wrench

Use just your hand to tighten it in place (avoid cranking down with a wrench, as that can damage the whole valve).

Set the new toilet tank valve

Look to see that the critical level (where the grey meets black, on this model) on the new valve is 1” above the top of the flush valve. This is required to meet code in the United States.

Install metal clip closer

Step Seven: Install clip

Install metal clip securely on top of flush valve directly under the tube.

Gently bend tube

Step Eight: Attach tube

Gently bend tube downward so end will line up with metal clip. Cut the tube if necessary so that a gentle, non-kinked curve in the tube occurs. This tutorial required trimming off more than half of the original tube. This is completely fine; what’s important is the smooth path of the tube from the valve attachment to the metal clip in the flush valve.

DIY Toilet Repair-connect
DIY Toilet Repair-water on

Step Nine: Reconnect water

Reattach the water supply line to the new valve, under the tank. Use your hand to tighten, and avoid using a wrench.

Turn water supply knob

Turn water supply knob back on.

Flush the toilet several times

Step Ten: Flush and check

Flush the toilet several times, checking for normal water flow, and no leaking, in three critical areas: the water supply connection at the bottom of the tank, the water flow from the new valve’s tube into the flush valve, and the water line at (or, rather, below) the new valve’s critical level.

Check the tanks valve

If you’re checked out at all three places for leak-free and accurate water flow, congratulations! Your toilet fill valve replacement has been successful, and you should be ready to use your “new” toilet worry-free.

DIY Toilet Repair Fixed