Jammed stopcock - what are my options

molinari

molinari

molinari

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I need to replace a shower mixer which has stopped working, and I have the instructions on how to do that. It seems fairly straight forward but I need to turn off the water before I start, and as there is no isolation for the shower, I need to turn of the mains water. However, the inside stopcock hasn't been used for years so has jammed open, and it won't turn at all. It's awkward to get to under the floor, and I have tried some WD40 on it, but it won't budge at all.

I believe there is a stopcock in the pavement at the front of my property, so if I get a plumber to replace the inside stopcock, will he just turn off the stopcock in the pavement to do the work?
Obviously a working inside stopcock is important but the fact that it's awkward to get to, I'm assuming I'll also have to lift the flooring in the hallway to get to it, which will be a nuisance and costly. So am I allowed to turn off the water from the pavement, replace the shower mixer, then turn the water back on?
 
molinari said:
I believe there is a stopcock in the pavement at the front of my property, so if I get a plumber to replace the inside stopcock, will he just turn off the stopcock in the pavement to do the work?
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The plumber did exactly this when he changed the stopcock at my mums house the other year.

I got him to replace the seized, awkwardly located one with a Surestop so that the remote switch could be placed somewhere much easier to access in an emergency.
 
I have a friend going through this as we speak. Local water firm dug up outside to replace his outside tap as that was seized too. Now he can isolate and fix inside tap.

Rule of thumb with any tap like this is always undo fully then tighten by a quarter turn. Theoretically that's just enough to break the seal the next time you come to it.
 
dLockers said:
Rule of thumb with any tap like this is always undo fully then tighten by a quarter turn. Theoretically that's just enough to break the seal the next time you come to it.
Click to expand...

Yeah this definitely helps. Closing it every 6 months or so to keep it moving isn't a bad idea either. It's certainly not something you want to find seized in a panic when you have a burst pipe or something like that.
 
paintguy said:
The plumber did exactly this when he changed the stopcock at my mums house the other year.

I got him to replace the seized, awkwardly located one with a Surestop so that the remote switch could be placed somewhere much easier to access in an emergency.
Click to expand...

Ahh! So that is what that thing under the sink is!! I thought it was some kind of isolation switch for the cooker :D
 
molinari said:
I believe there is a stopcock in the pavement at the front of my property, so if I get a plumber to replace the inside stopcock, will he just turn off the stopcock in the pavement to do the work?
Click to expand...
Yes. Our house's previous owner left us a right **** show of a plumbing. The stop **** was leaking and jammed. Then there was a water filter that looked like it hadn't been touched for 20 years. :(

It prompted me to do an complete rebuild of the bathroom, so was able to rip the whole lot out, moved the stop **** to a better location and fitted a new charcoal filter with proper isolation valves so it could be changed easily.
 
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andy_mk3 said:
Yeah this definitely helps. Closing it every 6 months or so to keep it moving isn't a bad idea either. It's certainly not something you want to find seized in a panic when you have a burst pipe or something like that.
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Advice definitely follow, now and again close and back it off a 1/4 of a turn. :)
 
I dug the tap out in the road a few years ago . cleared soil from arouind the tap then thought here we go and tried to undo tap - it went straight away so few ups and down - WD 40 everywhere then replaced the concrete squares - once at street level I put a 4" sewer pipe over tap and cut it off level just under the lid- this was to stop soil building up - Now put the three foot T bar on it every year to make sure it's still lose. I also check stop tap under the sink - this has a tendancy to go stiff but always get it to turn.

Bloke up the road asked a water board worker to undo his while he was next door - he put the T bar on and around it went - It didn't take him long to realise it had gone boobs up - Tap was still stuck solid but he had turned whole body and it had come out of plastic pipe - It was running for two days.
 
I've got exactly the same problem the main inlet under the sink is completely seized I thought someone would come up with a solution like hit it with a hammer or blowtorch it, guess I'm stuck with it!
 
Awesome, thanks for the replies and advice. I will probably just turn off the water at street level to replace the shower mixer, then get a plumber to do the same and replace the inside stopcock sometime next year. Once it has been replaced, I will definitely make a note to close then open it every now and then to make sure it doesn't jam up again.
 
Blackjack Davy said:
I've got exactly the same problem the main inlet under the sink is completely seized I thought someone would come up with a solution like hit it with a hammer or blowtorch it, guess I'm stuck with it!
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Problem is if you hit it with a hammer you could break it and then you're screwed as you'll have full pressure water gushing into the house, best advice would be to isolate at street level and see if you can lever it loose, be careful though as too much beef could end up wrecking your pipes seal on the stopcock
 
molinari said:
So am I allowed to turn off the water from the pavement, replace the shower mixer, then turn the water back on?
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In short, yes.... just don't break it, please, as my guys have enough work to deal with at the minute!

"To protect your home, you should always have a working inside stop valve. Use this as the main way to turn your water on and off.
Your outside stop valve is also known as your stopcock or stop tap. It controls the cold-water supply going into your home. You should only use your outside stop valve in an emergency, for example if you have a leak on the supply pipe between the inside and outside stop valves".
 
WD40 wont help unless its an external leak that has caused the outer handle to sieze

The issue is that crud builds up internally and means you cannot move the gate (normally stop cocks are gate valves, worth looking at a pic as most people think of ball valves when they think of a valve)
https://en.wikipedia.org/wiki/Gate_valve

There are multiple approaches-
The basics of slightly reclosing and turning on and off occasionally are basically preventative maintenance. Slightly reclosing means you can try to open and close constantly if its stuck as opposed to only trying to close.
If you dont do this you may find the valve will also leak when closed since the crud will be far more likely to be able to get stuck over time.

If its stuck then a few options and trying all over and over is likely the best approach to dislodge a build up

Slight heat if you can
Gentle taps with a hammer
Slightly releasing the packing nut so there is a little more movement in the "gate" too much and it will leak round the nut so if it starts to weep just tighten it back up
Trying to turn on and off constantly with decent but not excessive force

Its also handy to be able to lock the main valve body in place. A big set of adjustable spanners or a specific one for this purpose. So that majority of the movement you are applying is being directed to the internals of the valve itself and not trying to twist the valve body against the incoming/outgoing water pipes
 
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Anytime I've lived somewhere a plumber has needed to turn off the stop **** they always seem terrified if it's stiff :p

One mentioned they can snap off and flood the house, I think he used a drill with hammer action but seemed like it was a big risk
 
I’ve used the Aladdin stuff a few times. They’re pretty good.
Alternatively look at the a pipe freezing kit. Perhaps you know a friendly plumber locally? Not the kind of thing you’d buy for one job!!
 
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