What options for replacing a leaky 3/4" galv stopcock?

[diyAlex]

I have an imperial 3/4" galvansised steel rising main that is connected to a stopcock. This is all very old and every since we moved in (last year) the stop cock has dripped very slowly. The BG plumber has had a go at tightening it when they've been around to get the boiler on to homecare, but no joy there.

Thanks mainly to spudkey in my previous post (my mains water seems to be 27mm pipe?), I now know what the pipe size and material is.

So will I be able to easily connect some replacement pipe to that longscrew on the rising main ... or should I cut the pipe below that and connect a replacement something-or-other??

Rising main and stop cock

• diyAlex
• 7 Dec 2011
• 2

Close up of stop cock connected to rising main

• diyAlex
• 7 Dec 2011
• 2

 

[tim00]

1. where exactly is the stop-cock leaking? If it's leaking around the spindle you can loosen the stuffing box nut and re-pack it fresh and tight. First shut OFF water and drain down.
2. It's sometimes possible to pull the works from the valve and replace them. This would req. shutting OFF at the outside(in the ground) stop-tap.
3. Galvenised pipe builds up gunk and tends to fail after a few years, think about re-piping the system, including the ext. service pipe. The service is probably lead, but if it's galv. then it's on it's last legs.

4. You could cut the nipple below the valve, remove the off-cuts and the coupling and use a union, a new nipple and valve - hard going for DIY.

5. You could also eliminate as above and go back in with plastic.

6. From your pics i cant see the next connection above the valve or below it, if a connection is there and open to work on, then it might be better working to that fitting as it will give you a little more work room.

7. All in all, working with threaded pipe is not for DIY's.

 

[diyAlex]

Thanks for this info Tim

1. where exactly is the stop-cock leaking? If it's leaking around the spindle you can loosen the stuffing box nut and re-pack it fresh and tight. First shut OFF water and drain down.

It's on the spindle - where the handle's shank rotates whilst the body of the fitting stays still. It drips once every few minutes. Re-packing sounds like a good option. I suppose what worries me is dismantling it, but then finding that something is damaged and not being able to reassemble, and therefore being stuck with no water

3. Galvenised pipe builds up gunk and tends to fail after a few years, think about re-piping the system, including the ext. service pipe. The service is probably lead, but if it's galv. then it's on it's last legs.

Re-piping the system is definitely on the cards; it's just a question of deciding what to do when / what scope is manageable in one go. It's a project of a bungalow and we've only been here a year, so still much to do.

4. You could cut the nipple below the valve, remove the off-cuts and the coupling and use a union, a new nipple and valve - hard going for DIY.

5. You could also eliminate as above and go back in with plastic.

So, a plastic section replacing the existing stop cock bits, is that what you mean? Sounds like a good idea. I just tried searching for pipe fittings, but I'm not sure what words to use! I tried "plumbing imperial to metric / plastic" but couldn't really find fittings from that. Any ideas?

6. From your pics i cant see the next connection above the valve or below it, if a connection is there and open to work on, then it might be better working to that fitting as it will give you a little more work room.

No other connections. The pipe comes out of the ground and into the photo. And then above the photo it disappears as a single length into a wall cavity and up in to the loft.

7. All in all, working with threaded pipe is not for DIY's.

Thanks for the tip

 

[tim00]

1. Your best bet is to OFF the extn. stop-cock and drain down. Then loosen the packing nut with an adjustable. Then coil teflon packing rope around the spindle - once, or if there's room, twice. Nip up the nut with a little tape on its threads.
2. You could remove the works and replace the washer while you are at it.
3. Keep it simple, try the above first and see what happens. You dont want to get into dissimilar materials ( eg plastic ) with your skill level.
4. If you are doing up the bungalow, re-plumb and re-wire are essential before other small works.
5. Any other approach to the stop-cock will req. you to remove the carcassing - vertical 2x's.

 

[diyAlex]

Thanks Tim.

Re-plumbing is definitely on the cards. Re-wiring has already been done.

I have been reading up on imperial pipe, and discovered that the water board will take a sample free of water to determine if there is lead materials in the service pipe. So they're coming on Friday to do that.

At the moment, I'm thinking that I will replace the service pipe to metric, and sort out the stop cock then.

 

[tim00]

Samples of water are irrelevant, you can determine the water service entering the property either below the floor or at the exterior stop-cock box.
All modern, domestic piping is metric, no need to bone up on metric/imperial. Many utilities do no cost, lead free water service installations.