Changing stopcock internals.

[Mottie]

I need to change the stopcock on my workshop - it seems to have fallen apart inside but because it’s boxed in, it’ll be a major job to replace the whole thing. I can get to the main part of it though - see pictures. Could I just change the centre part over from the new stopcock? I need to either freeze the pipe somehow or do it live. There is another tap on the system on the way to the workshop stopcock and I’ve carried out a simple test. With just a workshop tap running it takes 13 seconds to fill a 2 litre jug. With the other outside tap running, it takes 28 seconds so considerably lower. Do you think it would be possible for me to change the centre bit over working live? If I did, would it be best to do it with all upstream taps open and the main stopcock on so that there's not too much pressure when I'm trying to screw the innards in, once the guts are changed over, then turn the stopcock off?

 

[Madrab]

You'll be lucky to get the internals loose without supporting the pipe or tap properly. They rarely come apart easily. Also the internals of the new tap may not be the same as the old (jumper/washer etc) and you wouldn't know until you get it apart.

 

[Justin Passing]

What you do is unscrew the crossbar, get a log socket an yer windy gun hammering thing set to undo, and you pray to god.

Switch the thing on, and your stopcock will be ripped from the pipework. Drenching and damnation will follow for 40 days and 40 nights.

Thus, you will have proved, that god doesn't exist.
But we all know that.

Can you find a place with access to the pipe?
(You will have thought about turning the water off in the pavement..... so assuming not...)
Buy a quarter turn full flow valve

Clean the pipe.
Reduce pressure if you can by opening upstream taps as you describe.
Get the new valve the right way round.
Open valve.
If you remove the top nut and lever it makes the thing easier to hold in grips etc
Put lever in your top pocket
Fit a stub of pipe and as short length of garden hose as you can, to reach outside /down a sink/ bog etc.
Clean the pipe.
Put the valve "in" end together just touch-tight, with jointing compound like Hawk Green/blue, Virgin White etc on the olive and make sure the thread runs free.
Cut pipe with a pipe slice - wetness - and shove the assembled valve on with the valve open, so water goes down hose to drain etc.
Do the nut up holding the valve in the grips (the hex is fiddly to use). Should only need about 1 turn.

Close valve with its lever you put in your top pocket.
Making sure there's swing room, replace nut on lever spindle.

A freezit can is ok for stationary water in a 15mm pipe.. There used to be cheap cans of coldth in the Pound Shop which worked, too.

 

[Mottie]

Yeah, no pavement stop cock. If it weren't for the bloody stopcock being behind that board, it wouldn’t be too bad a job. Going to have to steel myself for this. I’ll wait until I feel a bit braver…….

 

[Justin Passing]

UNfortunately the body screw threads vary these days too.

 

[Elkato531]

Going to have to steel myself for this. I’ll wait until I feel a bit braver…….

I would try to avoid attempting to replace the workings of the stoptap. Too much to go wrong with the chance of the new bits not fitting and no plan B.
Just remember to have someone video the whole thing and then post it on here
Seriously though, if you can freeze the pipe upstream, then you should try that.
Is there accessible pipe nearby? If so, it would probably be easier to cut the pipe and quickly put on a compression lever valve. (Have the valve open with a hose on the outlet). You will get wet but it should only take a few seconds.
If there is any plastic pipe upstream, a squeeze off tool can be used.

 

[Mottie]

I think when I get round to it, I’ll try cutting as much of that board away as I can using a jigsaw or mult-tool to see what I’m dealing with. The compression lever valve as a few have mentioned with a bit of hose on it seems favourite at the moment. I'll use the stopcock I bought to replace the one in my house when I do the kitchen as that has siezed in the on position. At least I can turn my house water off in the street.

 

[HERTS P&D]

Mottie, if you need a hand, let me know and I can pop over to you.

Andy

 

[Mottie]

You'll be lucky to get the internals loose without supporting the pipe or tap properly. They rarely come apart easily. Also the internals of the new tap may not be the same as the old (jumper/washer etc) and you wouldn't know until you get it apart.

I would try to avoid attempting to replace the workings of the stoptap. Too much to go wrong with the chance of the new bits not fitting and no plan B.

What you do is unscrew the crossbar, get a log socket an yer windy gun hammering thing set to undo, and you pray to god.

Switch the thing on, and your stopcock will be ripped from the pipework. Drenching and damnation will follow for 40 days and 40 nights.

Thus, you will have proved, that god doesn't exist.

Ha, cracked it - thus proving a God does exist!

Before I started butchering the pipework and 3/4" board to get at the stopcock, I thought I'd just see how tight the old internals actually were. Not very tight at all, as it turned out. Turned on the upstream tap to reduce the pressure, said a prayer to the God of plumbing and just went for it. Surprisingly, there wasn't the torrent of water I was expecting and the new internals were an exact match for the old one. screwed it in, job done.

Well, almost! I needed to move my water heater out of the way before starting and the minute I touched it, I had a jet of water coming from one the flexi pipes going to it so I'm going to replace both of them tomorrow. Still, I was expecting major aggro from this but its turned out to be a piece of píss.

 

[Justin Passing]

Lucky barsteward. Tell you what, try day trading!