3/4" imperial stopcock with odd fitting

[GlasWolf]

I've just replaced all of the 3/4" pipework in our late 60s house, and the only thing left is the stopcock itself. It has something similar to a compression fitting, but the pipe hardly inserts into the body of the stopcock at all, and the nut is taller than usual and has a rotatable brass bush inside it..? I think the pipe that was mounted in it before had a pre-formed ridge rather than an olive - I'm showing my layman's ignorance here.

I'm using a stub of 3/4" copper pipe and a 3/4" olive but can't get a weep-free connection. I'd rather not replace the stopcock itself if I can avoid it. Can anyone tell me if there's a better way to connect to it please.

 

[thomp1983]

A photo would make helping alot easier, you can take it on your phone then use the the attach files button below to upload it directly

 

[GlasWolf]

I can't disconnect it at the mo so not much to see, but this is it:

 

[CBW]

Didn’t really need a photo, it’s a manipulative compression joint, so either need to manipulate the pipe, renew the stopcock, or renew just above the stopcock.

Looking at the photo, it seems more like 1/2” pipework as opposed to 3/4”.

 

[GlasWolf]

Thanks Chris, new one on me. In my ignorance I cut the old manipulated pipe stem to remove the fittings, so I'm a bit stuck from that point of view. I'll maybe see if a local plumber can manipulate and install a new one otherwise I guess the stopcock will have to be replaced.

 

[Madrab]

Yup, as you compress the nut, the bush inside grabs the pipe and flares it onto the fitting making it watertight. Old school stuff that.

Shut off the ouside water and replace the whole thing would be my advice. Old stuff like that will be either 1/2" which is compatble with 15mm or 3/4" which isn't compatible with 22mm and will need a converter.

 

[denso13]

It's amazing the number of jobs you can do with the pointy end of a pair of footprints....

 

[GlasWolf]

Yes, I think I might just replace it. My instincts are that I shouldn't put pushfit before the stopcock - am I being paranoid? I have a speedfit 3/4" - 22mm adapter I could use, otherwise I'd need one of these.

As a side note I'm surprised how hard it is to get imperial fittings considering this average late-60s semi was fully fitted out with 3/4" pipework. Most of it steel too.

 

[Madrab]

It's usually all either swapped out or permanently converted with a 3/4" > 22mm solder fitting.

 

[AdrianUK]

It's amazing the number of jobs you can do with the pointy end of a pair of footprints....

View attachment 273166

I've often wondered why the end of the inner arm of the footprints is shaped like that! I know it must be for a reason... I guess I assumed it was for flaring out the open end of a lead pipe ready to insert a copper pipe & wipe a 'proper' joint.

 

[bsr]

Yes, I think I might just replace it. My instincts are that I shouldn't put pushfit before the stopcock - am I being paranoid? I have a speedfit 3/4" - 22mm adapter I could use, otherwise I'd need one of these.

You can buy 3/4 olives that fit into a 22mm fitting so you could buy a normal 22mm stopcock and one of the special olives.

3/4″ Imperial Brass Olive For 22mm Copper Compression Fittings

A brass olive to convert a metric 22mm compression fitting to the slightly smaller 3/4″

plumbinbits.co.uk

Personally I would replace with a full bore lever valve, I don't use stop taps any more. Better flow, no sticking and no leaking glands.

 

[JohnD]

Bear in mind that 3/4" BSP fittings do NOT measure three quarters of an inch at any point.

I think you might have 1/2" BSP fittings (which do not measure half an inch)

 

[GlasWolf]

You can buy 3/4 olives that fit into a 22mm fitting so you could buy a normal 22mm stopcock and one of the special olives.

Personally I would replace with a full bore lever valve, I don't use stop taps any more. Better flow, no sticking and no leaking glands.

I'm having trouble getting a plumber out in a reasonable timescale and I have one of those olives handy, so I'm seriously considering this and a Pegler lever valve from Screwfix.

 

[GlasWolf]

An update to this: I have my 22mm stopcock and copper metric/imperial olive ready, but have just scraped a patch of paint off the pipe going into the old stopcock and it looks like it's steel*. I tried a couple of compression fittings to 3/4" steel pipe before I pulled it all out and they always wept - is this doomed to failure? I have some water hawk this time instead of tape, which I'm hoping might help.

* There was a bit of tinned copper pipe (?) just above the stopcock, so it might be that.

 

[johnny2007]

I had the same problem with my house when we moved here.
We replaced the stopcock using a freezing kit because the street shut off valve was rusted and wouldn't move.