Cutting lead mains pipeI have a leaking stopcock which I need to replace. It's attached to 25mm lead mains pipe which come up vertically. I have a lea

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I have a leaking stopcock which I need to replace. It's attached to 25mm lead mains pipe which come up vertically. I have a lead to copper compression fitting to connect it up.

I was about to remove the old fitting, but dont have a spanner big enough for the nut, so I almost took my angle grinder to it as it's close to the wall and a hacksaw will be a faff, but I suddenly read that it was dangerous to cut lead. Is this the case?Pic:

1663078772756.png
 
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Not saying it isn't but are you absolutely sure that's lead? It just because that elbow really looks like maleable iron, which would make the pipe more likely to be Low Carbon Steel (LCS). You wouldn't normally have elbows like that on a lead pipe.
 
Not saying it isn't but are you absolutely sure that's lead? It just because that elbow really looks like maleable iron, which would make the pipe more likely to be Low Carbon Steel (LCS). You wouldn't normally have elbows like that on a lead pipe.
It could well be actually. I'd scraped away the grime and it's a silvery colour but not anywhere near as soft as another bit of scrap lead i have.

If this is steel, how does one connect to it? Same fitting?
 
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I agree with Rob, looks like LCS. scratching the pipe is hardly conclusive ;)
 
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It could well be actually. I'd scraped away the grime and it's a silvery colour but not anywhere near as soft as another bit of scrap lead i have.

If this is steel, how does one connect to it? Same fitting?
No, you have remove the stopcock and use a threaded fitting that attaches to big nut you haven't got a spanner big enough to undo.

If you cut that pipe, you will need to rethread it and use a threaded fitting which will be tough to do as the pipe looks tight to the wall.
 
Use a magnet, if it sticks it's LCS.

Where is the tap leaking? It may be easier to service the tap if you can crack the head gear off of it (prob stilsons and support the back of the tap). Otherwise you will need to use an adapter to get the LCS to metric and a small piece of pipe for the new tap/valve

If it's weeping at the gland nut then turn the tap off, loosen the gland nut, a number of turns of PTFE tape around the spindle and tighten the nut back up, is only temp and good for a few uses of the tap on and off and then it will start to weep again.
 
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Use a magnet, if it sticks it's LCS.

Where is the tap leaking? It may be easier to service the tap if you can crack the head gear off of it (prob stilsons and support the back of the tap). Otherwise you will need to use an adapter to get the LCS to metric and a small piece of pipe for the new tap/valve

If it's weeping at the gland nut then turn the tap off, loosen the gland nut, a number of turns of PTFE tape around the spindle and tighten the nut back up, is only temp and good for a few uses of the tap on and off and then it will start to weep again.

The problem is that it does not have a gland nut where modern stopcocks do. It is leaking at the point the tap stem goes into the stopcock however this part has no nut as it's just round (see below numbered #1), the only nut nearby is a lot further back (marked #2)

1663082677661.png
 
If you don't want to buy a big enough spanner to undo the nuts onto the stopcock, then is your spanner big enough to undo the the head nut (label 2 in your photo)? You may have some success in removing the whole tap head and putting PTFE tape onto the spindle where it passes through head to add to the old hemp and grease packing. This will stop the leak, but i wouldn't then use the stopcock again as you'd likely destroy the seal so you'd have leave it turned fully on and then insert an additional stopcock down stream.

I'd just buy a big enough spanner and a correctly sized quarter turn ball valve to replace the stopcock with.
 
If you don't want to buy a big enough spanner to undo the nuts onto the stopcock, then is your spanner big enough to undo the the head nut (label 2 in your photo)? You may have some success in removing the whole tap head and putting PTFE tape onto the spindle where it passes through head to add to the old hemp and grease packing. This will stop the leak, but i wouldn't then use the stopcock again as you'd likely destroy the seal so you'd have leave it turned fully on and then insert an additional stopcock down stream.

I'd just buy a big enough spanner and a correctly sized quarter turn ball valve to replace the stopcock with.
I'm happy to get a spanner, i just have no idea what ball valve will fit that fitting if it's really old. The steel pipe is around 25mm (i guess 3/4 inch), would a new valve be the perfect match?
 
I would imagine it will be 1 inch or 3/4 inch bsp. It'll be a remove it and take the old stopcock to a plumber's merchants job to find the right size replacement ball valve and then adjust the downstream pipework to fit.

If you're not confident doing the above, then it's a job for a plumber if you need the water on again quickly.
 
I would imagine it will be 1 inch or 3/4 inch bsp. It'll be a remove it and take the old stopcock to a plumber's merchants job to find the right size replacement ball valve and then adjust the downstream pipework to fit.

If you're not confident doing the above, then it's a job for a plumber if you need the water on again quickly.
But the stopcock wont fit directly onto that big nut, as stopcocks have a compression fitting which is incompatable with the nut. I very much doubt there will be stopcocks which will fit directly onto that nut anymore!

I'm assuming that what is going to be needed is a threaded fitting adapter which goes into the big nut, and can then be fitted directly to a new stopcock.
 

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