Trombone Toilet

[Mr G]

Why does my toilet sound like a trombone every time i flush it.
(please keep answers clean )
The noise lasts approx 1 minute
I know there must be air somewhere in the pipe but what causes this and how do you fix it

any help appreciated

 

[mole]

Are you able to stop or modify the noise by holding the ball valve asembly - often noise is caused by inadequate support of the valve assembly. Ensure that the threaded long bolt, that braces the assembly against the wall of the cistern, touches the wall and that the locknut is tightened to prevent the boly coming loose. All the foregoing assumes you have a plastic valve assembly and not an older type Portsmouth one.

 

[taydo]

it is called water hammer quite possibly due to the ball valve washer failing. it might be a good idea to replace the ball valve for what they cost.

 

[Mr G]

Thanks Taydo and Mole

I shall have a go this weekend and see if it works

 

[ChrisR]

It isn't water hammer exactly, it's the washer vibrating! Changing the washer will fix it for a couple of years at least. Changing the whole valve for a brass one may be a better fix but hardly worth the effort.