Toilet cistern leaking into pan

[dena007]

Hi,

I managed to fit a new 'Fluidmaster 400UK' cable dual flush cistern back in February. Everything fine until recently when we thought we had a ghost! Toilet flushing by itself - anyway, have turned off water, and the whole cistern has slowly drained back into the pan.

It must be leaking back through the very bottom of the valve - have tried to take a few piccies which may help

The small washer which is enclosed at bottom of valve seems to be perfect, so can't understand why, all of a sudden, it's not watertight any more - any ideas?
View media item 38621View media item 38619View media item 38620

 

[seco services]

so can't understand why, all of a sudden, it's not watertight any more - any ideas?

Rubber seal scaled or deformed. (unuseal in that short time)
Cable sticking and not returning fully.

 

[dena007]

I've inspected the washer but it looks fine? Also, it is contained within the valve as per 1st pic, so how would I ever replace it?

I'm pretty sure the cable isn't sticking

Any other ideas?

 

[seco services]

If i remember the plastic clip comes off the bottom the the seal comes off.
sometimes you can pull them over the clip.

I'd have to check one of mine to get the brain in gear.

 

[Charnwood]

For the record the flush valve is either a 550073 or a PRO550UK.
The inlet valve is the 400UK.

The washer comes off, replacements are available for about a fiver:
http://www.enviroflush.co.uk/flush-valves.htm
http://www.toiletspares.co.uk/flush_seals_27.html

Is the valve still tight in the cistern? Water could possibly be leaking through the connection and not necessarily through the valve itself.

 

[dena007]

For the record the flush valve is either a 550073 or a PRO550UK.
The inlet valve is the 400UK.

The washer comes off, replacements are available for about a fiver:
http://www.enviroflush.co.uk/flush-valves.htm
http://www.toiletspares.co.uk/flush_seals_27.html

Is the valve still tight in the cistern? Water could possibly be leaking through the connection and not necessarily through the valve itself.

Thanks - I ended up taking the part back to B&Q (stiill had receipt) for them to advise on new washer, but, they didn't seem to stock them, in the end, sales assistant just swapped the whole unit for a new one!

Fitted it & now works fine.

Thanks all