Flush valve leaking into toilet

[Fredstudio]

Do you change the flush valve washer in this instance, or unit?

 

[Wayners]

So it keeps filling up? This causes water to overflow over the syphon and run down the toilet pan.
If you adjust float will it stop?

If it keeps running change the washer if you can locate the correct replacement

 

[Fredstudio]

It keeps running in to pan, water level below overflow

 

[ChrisJP]

You need to find out and then explain whether it's the flush valve at the base of the cistern that is leaking (assuming you don't have an older siphon flush), or whether the fill valve is not shutting off properly so the cistern is overflowing. Modern cisterns overflow into the toilet pan, so either of these faults will result in water continually running into the pan.

 

[Fredstudio]

Thanks it's this valve I think I have found the correct washer anyone swapped the washer on these flush valves. Is an ideal standard toilert so want to avoid stripping the cistern down.