Loud noise after flushing toilet cistern

[ey143]

There is a loud dull vibrating sound that has started coming from the cistern when I flush it. It stops when the ball valve has closed the water supply. But because of the vibration it feels like it's coming from underneath the bathroom floor as it can be heard from anywhere in the house.

Any thoughts?

 

[sooey]

It's water hammer, very common. It's caused by the washer in the toilet filling valve vibrating, you need a new washer or a new filling valve.

 

[ey143]

Thx. First time I've come across this problem in my 36 year life time.

Is this relatively easy to replace as a diy job?

 

[denso13]

Turn the flow down at the isolating valve if there is one. May help in the short term.

 

[ey143]

Yes that's exactly what I've done this morning. Still makes a small sound when I open and close the basin tap though whilst the cistern is filling. Ok for a temp measure (which in my case means a few years until a different problem occurs like the siphon diaphragm which I only recently replaced!)