W.C. cistern leak

[connelsey]

Following a burst water main down my road a week ago.

My cistern has started to leak despite having adjusted the float arm downwards and replacing the washer for the ball valve. I've tied up the float arm and can still see a small drip entering the cistern.

Can anyone suggest why this should be happening and how I might stop the leak?

Many thanks
Connelsey

 

[ChrisR]

Check there isn't some dirt embedded on the valve seat.

 

[connelsey]

Thanks for your help here Chris, I'll give it a clean out with an old tooth bush.