Multikwik Multiflush Cistern Overfilling

[OldSoul71]

My regular plumber wasn't available so thought I'd have a go.

Long story short, flush button broken and couldn't get a compatible replacement. So I bought a Multikwik Multiflush.

To my surprise, I successfully installed it but when I flush, the cistern continues to fill.

Apparently, the height of the overflow can be adjusted but it doesn't seem to want to sit high enough. Locking the overflow also doesn't help.

Tearing out what's left of my hair wondering what I'm doing wrong and why the overflow won't do its job.

 

[ShaunCorbs]

Dirt in the ball valve

 

[Deleted member 120897]

Dirt/debris on the flush valve seating, on the cold inlet as Shaun suggests, or the button is too long - unless it’s a cable type?

 

[OldSoul71]

Now resolved. Thanks for the replies. No idea what the deal was. Slightly tightened the hose connector to the Fluidmaster and it started working as it should. Slight weeping from the underside of the cistern where the fluidmaster comes through but I can live with that for now.