Niagara valve problem?

[rsk289]

I have a Dudley Niagara valve fitted in a Dudley concealed cistern. After flushing there is a very small trickle of water into the toilet pan, which is fairly hard to see after a while but wets paper very easily. I don't know if this is normal or not, but it is now causing a stain on the ceramic which is unsightly. I have two others in the house which don't do this.
I've removed the Niagara to service it, which made no difference, so have now changed the entire Niagara valve parts (swapping over into the old valve base). Everything looked clean and smooth whilst it was apart, but the problem (if it is a problem) remains. Should I try changing the entire valve including base, which will be difficult positioned behind the panelling (and messy), or accept that this is normal for a Niagara?
Thanks,
Roger

 

[ShaunCorbs]

water level ok? and no not normal

 

[rsk289]

water level ok? and no not normal

Yes, water level's OK. It's working fine apart from the faint trickle of water.

 

[Bronze_tap]

Check the base for any scratches/contaminants in the area where the valve's rubber washer forms a seal. If any limescale there - try cleaning with cilit bang/black domestos. Wear gloves and wipe in concentric motion.

Usually you need to remove the top part of the walve assembly to be able to acceess the base, where it seals against the rubber washer.

Once I had a bit of thread lodged there, causing a trickle leak into a pan and periodic cistern topups.

 

[Bronze_tap]

Check the base for any scratches/contaminants in the area where the valve's rubber washer forms a seal. If any limescale there - try cleaning with cilit bang/black domestos. Wear gloves and wipe in concentric motion.

Usually you need to remove the top part of the walve assembly to be able to acceess the base, where it seals against the rubber washer.

Once I had a bit of thread lodged there, causing a trickle leak into a pan and periodic cistern topups.

 

[PlumbBobBob]

guess it is sorted by now