How to fix a leaking Toilet Cistern

If your  Toilet is leaking or running it is fairly easy to fix. Sometimes the Valve that stops the water filling the cistern needs adjusting. How to fix a leaking Toilet Cistern. This will stop the water overflowing into the bowl. Sometimes the valve that stops the water filling the cistern is worn and needs replacing. Sometimes the Washer that stops water flushing into the bowl is worn out and needs replacing.

Sometimes it is worth a few dollars to fit a new inlet valve assembly. Not difficult and all the instructions are on the box. The new ones are much quieter and are easy to fit as all the instructions are on the box.

Follow the instructions below for all three most common fixes.

Older Ball valve arms can be gently bent down by holding the arm near the pivot point and pushing the arm near the Ball downwards just a little. Other Plastic arms have a small adjusting screw that can be turned clockwise to lower the end of the arm.


Newer Float arms have a water height adjusting screw that turns clockwise to lower the arm. It might need un adjusting (anti clockwise first, then insert a small piece of plastic about 2mm thick under the screw then adjust cloackwise. Trial and error will get you there.


If the water continues to fill the washers will need replacing. Unscrew the Inlet valve cap after removing the metal pin using pliers. Gently twist and pull it out. The cap can be quite tight, so hold the lower part of the inlet valve while you unscrew (anti-clockwise) the cap.Look carefully at the next piece, maybe mark it with a pen on one side so that it gets refitted the same way it comes out, You will see the washers that need replacing. There are different types so off to the hardware for new ones.(see photos for ezamples. Take the old ones with you as a sample.
When fitted re-assemble Washer knob, Cap, arm, Pin. The arm may need adjustment till the water level is just below the overflow pipe height.

If the water is running into the bowl the outlet washer is another one that you can replace.You will need to remove the middle section that the water flows down thru the flush pipe. There are many different types and  ways to remove them. Too many to list. Have a look and you should be able to work it out.

Just a word of warning. I have replaced washers & valves and still had problems. So if your cistern is fairly old consider a new cistern.Might be cheaper in the long run.