ISOLATION VALVE LEAKING SLIGHTLY FROM SCREW

[dimmy]

Hi!...why is that the simplest of diy jobs turn out to be the ones that go wrong!...? I wanted to change the tap head (including the brass ferrel innard parts inside on my kitchen hot tap. This was because the tap would only turn about one revolution and the flow was either weak then strong (all other taps have good pressure). Anyway so the first thing I did was gave the isolation valve screw under the sink a quarter turn so it was horizontal across the pipe. This turned the supply OFF to the tap BUT the isolation screw kept leaking..drip drip drip. The irony is I couldn`t get the tap off anyway after removing the cap and screw as it has been there for years and it was solid... so I reassembled tap as it was. After fiddling with the isolation screw for several minutes I finally got it to stop leaking (fingers crossed)....and the strange thing is the hot tap turns 3 revolutions like it should do and the flow is great!!!..even though i did not renew the innards!!...So i have 2 questions please.
1. I have read somewhere that if you do not get the isolation screw on the valve in EXACTLY the right place it can leak,..and you have to get it spot on or it will leak..is this true...AND do you think as it hasn't leaked for an hour with the tap on and off i will be ok?
2. Is it possible that some limescale or crud was caught in the isolation valve and i have released it so that now the flow is great although i don`t see how if i did dislodge some limescale that would make the tap have more turns now!???

Many thanks!

 

[Harvest Fields]

Simplistic of answers here, but

1 - NO

2 Maybe but I doubt it.

3- I know there is no 3 but I have created one to tell you to change the isolatation valve.

 

[Best]

Just buy a new isolating valve - a slotted screw full flow type (which has white ptfe seals at inner ball part) or similar valve.
Or use same sort of valve, but a lever type.
The cheap isolating valve you probably have, no doubt has a rubber seal and leaks often if touched. Just leave it if no leak until you get chance to replace.
You might have had the valve blocked, which isn’t surprising due to the small bore

 

[WaterTight]

If it doesn't leak for a few hours after you turned it back on I would estimate you have a 95% chance of having got away with it.

I would raise this to 99% had it not taken several minutes of twisting and turning it to stop it leaking but rather only dripped momentarily when turning off and not dripped when turning back on.

 

[rpm]

Hell, those buggers leak if I so much as think of turning them off .

 

[Harvest Fields]

Hell, those buggers leak if I so much as think of turning them off .

If they are not shiny and sparkling I leave them well alone.

 

[Best]

If they are not shiny and sparkling I leave them well alone.

Were you once a jewel thief?

 

[Harvest Fields]

Were you once a jewel thief?

Maybe in a past life.

 

[Best]

Maybe in a past life.

....So from one robbing profession, to another robbing profession?

 

[Harvest Fields]

..So from one robbing profession, to another robbing profession?

Huhhh ??

 

[dimmy]

Hi thanks for the advice...just an update... these isolation valves with the screw are mostly crap...I much prefer the ones with the thumbturn peg. 12 hours later the screw/valve is still bone dry with the tap running or not. Before I tampered with the valve every morning there was hardly any flow from this hot tap..until a few a few seconds of turning the tap off and on...then the flow came back about 50%. This morning the flow is instantly 100%. (this kitchen hot tap is pressurised as I live on the 3rd floor and there is a communal pump on the ground floor. Also my internal hot supply is pressurised as the flow comes from a pulsacoil electric boiler with a built in pump. It could be my imagination that there are more turns/revolutions on the tap now ..due to the new strong flow. I am convinced that I must have dislodged some limescale/crud from the valve area when I tampered with it...I live in a high limescale area..as my washing machine sometimes has flakes of limescale in the drum. I couldn't shift the tap head when I tried to remove it so I can`t see how I dislodged any limescale etc there. In a roundabout way I seem to have cured the original weak flow problem from the hot tap..the fact I couldn`t get the tap off doesn`t matte now!. I Will keep any eye on the valve ..do you think it could still leak ..?..pending new replacement mixer taps and valves..thanks!