Adjustment on inlet valve

[Mr M]

Water is filling-up too high in the cistern and is then running into the overflow pipe on the flush valve. I assume I need to make an adjustment on the inlet valve to cut-off the water supply before it gets too high in the cistern but how do I do it?

 

[Alec_t]

If it's only recently that the inlet valve has been misbehaving then it probably needs a new diaphragm.

 

[Mr M]

Just to clarify, its not filling continuously. Once the water level reaches the top of the overflow pipe, the cistern keeps filling for a minute or two and then the water does cut-off so that the cistern stops filling. The water trickles into the pan until the level in the cistern gets down to being level with the top of the overflow pipe.

I thought I would have just needed to adjust something on the inlet valve to reduce the amount of water that was being allowed to enter the cistern so that it then wouldn't reach the top of the overflow pipe on the flush valve. Are you saying it's not possible to adjust the inlet valve then so that it allows less water into the cistern?

 

[JimCrow]

 

[Madrab]

Yup, @JimCrow beat me to it, its the actual body of the fill valve body that adjusts by sliding up and down, just need to drop the height of the valve a little.

 

[Mr M]

Thanks for taking the time to respond.

I've now managed to twist the body of the inlet valve and have lowered it down. It was all a bit tight inside the cistern but I lowered the body of the inlet valve by about half an inch each time and then refilled the cistern but the water was continuing to fill upto and then into the overflow pipe on the flush valve.

I have now lowered the inlet valve to about as low as it will go but the same thing is happening. The water continues to fill the cistern and then shuts off after about 2 minutes.

Also, I noticed that with the inlet valve as low as I could get it, the whole unit is now totally submerged when the cistern is filled with water? Is this correct or should the water be cutting off before it gets totally submerged.

Based on the above, is a new inlet valve now required?

 

[terryplumb]

Yes ,new float valve needed.