Turn Off the Water Supply to a Toilet

When fixing something in the cistern/tank of your toilet, it can be real problem if either the shut-off valve does not work, or there is no shut-off valve at all. The following will detail how to drain your toilet tank without shutting off the water to the entire home.

Steps

 * 1) Look for a faucet/tap on the pipe that leads to your toilet cistern/tank. If you find a valve, first inspect the condition of the water supply valve which allows water to fill the toilet tank (shown by a red arrow in the photo). This is usually a 90 degree angle valve. Overtime due to minimal use, this valve can become very stiff and brittle. Forcing it closed, and then fully open again can cause weeping, leaks, and breakage. Carefully attempt turning the handle clockwise (without over-forcing) to turn off the water to the toilet.  If you've successfully turned it without any problem, you can skip the remainder of these steps and continue with your repair job.
 * 2) If you have an older system (pre-1970s) your toilet may not have a shut-off valve. Take the lid off the tank, and find the float (1). It will be a small container of air, designed to float on top of the water in the tank. When it floats to a certain height, the valve stops letting water into the tank; when you flush the toilet, the float falls with the water level and reopens the water valve. This allows the toilet to refill, stopping when the float reaches the correct height again. To prevent water refilling the tank, you must secure the float to prevent the valve from opening after a flush.
 * 3) Try slipping a narrow length of wood under the lift arm/float lever (3) and straddling the board across the tank (front to back) to hold the lever up. If the sides of the tank are too high to do this, then straddle the board above the float lever, and wrap a length of stiff wire around both the float arm and the board to hold the float in the fully upright position.
 * 4) Flush the toilet to empty it. The tank should empty, while the wood/wire strapping holds the lift arm up preventing the valve from refilling the tank.
 * 5)  After the completion of your repair work, simply remove the board and or strapping to allow the float to refill the tank.

Tips

 * If the water supply valve under the tank is all crusty or there is a lot of rust, you shouldn't turn the valve unless you are prepared to replace the valve. An old supply line shut-off will often leak if it has not been used in many years.
 * To attempt adjusting an older valve, it would be advisable to first wrap the valve in cloth and grip it firmly with a heavy pipe wrench, to prevent the valve from twisting the water lines while forcing the tap in or out. Trying to force an older valve open or closed, can easily unseat the fittings of the connecting water lines, thus causing leaks.
 * If repair work is required inside the tank, it might be a good time to consider also replacing the supply valve.

Warnings

 * This method will only help with minor repairs inside the tank. Any major plumbing should be undertaken with the water supply completely turned off.
 * Carefully inspect the condition of the water supply valve which allows water to fill the toilet tank (shown by a red arrow in the photo). This is usually a 90 degree angle valve. Overtime due to minimal use, this valve can become very stiff and brittle. Forcing it closed, and then fully open again can cause weeping, leaks, and breakage.
 * Another common problem with adjusting this value is noise. An older value can squeal, rattle and vibrate as pressurized water moves through an improperly seated value with worn parts. This can occur every time you flush.

Things You'll Need

 * A length of wood, 14 to 18 inches
 * A length of stiff wire or coat hanger

Related Tips and Steps

 * How to Fix a Running Toilet
 * How to Unclog a Toilet
 * How to Install a Basement Sump
 * How to Clear Standing Water from a Sink
 * How to Repair a Delta Brand Kitchen Faucet
 * How to Seal Around a Basin or Bathtub with Silicon