How do I get a new flexible hose to engage without leaking to inlet valve bottom entry?

[bomitie]

The inlet valve bottom entry to toilet cistern developed a drip that flowed under toilet and dampened grout on tiles. Initially I could not figure where leak was so fearing it was an underfloor pipe I called out the original plumber from 13 years ago. Turns out it was the inlet valve to cistern. Plumber replaced pipe with a new flexible hose, told me keep and eye on it, charged me and left. A few hours later I noticed it was still leaking at inlet. New hose was finger tight, plumber not responding, may be too busy, doing a full house apparently. Can I assume the plastic thread on the inlet is kaput, I tried plumbers tape, I tried fernox etc all to no avail. My eyesight is fading so I am not even sure new hose is screwed on square. I had a good look at inlet valve and I'd say I can replace it myself but need to get correct one. . I am attaching a few images, of valve by R&T., inlet screw on to cistern, its got some tape on it since removed, and the new hose fitting. Can I assume its 1/2 size? And a final pic of a go daddy with a brass fitting, is this ok?

And as I have the weekend any final tips on how I can make existing leak free!!

 

[rpm]

If the nut on the flexi is tight and you can still move the flexi then it is not right. When fitting nut to inlet valve turn it anti-clockwise until you hear/feel a click then tighten as normal. I go handtight then nip it up with a spanner whilst making sure the valve stem doesn`t turn.

 

[king of pipes]

Change the inlet valve for a brass tailed version. Kop

 

[bomitie]

Thank you both, I changed it to a brass version and all good now. Why do they use plastic? Still no news from plumber but the item only cost me €9 euro and I am sure he would have charged a bit more to change it and I learnt a bit about dual flush cisterns.

In a word I am " delighted" with myself. SWMBO is gobsmacked.

 

[Stigster]

Well done! If I am ever supplied with a valve with plastic thread to connect to a metal nut I always advise against it. These plastic threads especially on toilet inlet valves are a liability. The plastic becomes brittle and eventually cracks sometimes causing a major disaster.

Whoever thought it was a good idea to make these valve tails in plastic wants taking out back and having a word with!

You've absolutely done the right thing fitting a valve with a brass shank instead of another plastic one. Sometimes the plastic thread even looks OK but it can have a crack between the threads and leak everywhere.