Tightening 1/2" iron coupli

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The spindle on the seized lower stopcock in the photo below is restricting access to the floor space in the cupboard where it is located. I want to turn the stopcock so that its spindle is inline/parallel with its pipework.

I've tried undoing the stopcock/galv coupling a little over 1/8 of a turn but it leaked so I tightened it back up.

I'm considering tightening the unions (a little over a 1/4 of a turn) but I'm concerned that this might split something and cause a major leak.

Please can someone advise?

The incoming pipe is 1/2" iron (19.33mm O/D) to 1/2" female x 3/4" male reducer to 3/4" x 3/4" coupler. I'm not sure if the stopcock itself is 3/4" or 1/2" with another 1/2" x 3/4" reducer, or if it's a male or female connection. Assuming it's the original, it was installed around 1962. Hope that makes sense?

If tightening the union(s) is unlikely to split something, which is/are the best joint(s) to tighten e.g. pipe to reducer or reducer to coupler or coupler to valve or perhaps a little on each?

Eventually I want to move all the pipes to make the area more useful but for now turning the stopcock will do.

Any help will be much appreciated.

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Personally, i wouldn't touch that stopcock or the coupler. The joints have been made with hemp so disturbing them is likely to make them leak.

Best thing you could do would be to replace the stopcock, but that will require you being able to isolate the mains water outside the property.
 
1. If you can't see what is below the floorboards, I wouldn't touch it. If its a right angle bend below, shouldn't be an issue. However if it has another straight coupler, you could end up splitting / breaking that and giving yourself a difficult to control leak.
2. If you can secure any joint below the floorboards, you could:
2a. Isolate the water supply (at the meter?).
2b. Remove the headworks from the old stop cock so that the body will turn.
2c. Remove the compression fitting to the copper above the stop cock.
2d. Unscrew the stop cock and all adaptors etc to leave the male threaded part of the pipe above the floorboards. You might need heat and some decent grips / Stilsons.
2e. Use a female iron to compression adaptor to provide a compression output. If the pipe is 3/4" something like Screwfix 38542. If 1/2" then Screwfix 5725G.
2f. Clean up the threads on the pipe end with a wire brush. Then use either PTFE tape or Loctite 55 wound round the threads ( in a direction of tightening the adaptor) and fit the adaptor. If you use Loctite 55 (which in my opinion is better), rough up the pipe threads gently with a file and apply as directed on the container. You could also use Loctite 577 or Flomasta Pipe Seal (Screwfix 4373J), but if you do, make sure male and female threads are clean and grease free.
2f. Either bend up a piece of 15 mm copper pipe to run from adaptor to the new stop cock, or a bit of 15 mm copper and a 90 degree elbow (compression if you don't want to solder).
2g. Turn on the water again.
3. Or you could consider putting in a false floor above all the pipework. Probably a lot less bother and you won't lose all that much space.
 
Personally, i wouldn't touch that stopcock or the coupler. The joints have been made with hemp so disturbing them is likely to make them leak.
Best thing you could do would be to replace the stopcock, but that will require you being able to isolate the mains water outside the property.

Isolating the mains water outside the property wouldn't be a problem; have done it several times already.

A replacement (2nd) stopcock has already been fitted downstream of the original one, see photo. I understand that the thread on a 15mm compression fitting is 1/2" BSP. If the original stopcock is 1/2" could I simply remove both stopcocks then discard the nut and olive from the 2nd stopcock inlet and screw it directly into the 1/2" female socket where the original stopcock inlet had been fitted using suitable sealant/PTFE/hemp? I could then fit a scale reducer in the horizontal pipe. This would be a temporary solution until I change all the pipework.

If the original stopcock is 1/2" iron/BSP parallel and not 3/4" or tapered could I simply discard the compression nut and olive from the inlet side of the 2nd stopcock and screw it directly into the 1/2" iron female connection inside the (rising) coupler , then redo the pipework to include a scale reducer that I have in the horizontal pipe where the 2nd stopcock had been.


1. If you can't see what is below the floorboards, I wouldn't touch it. If its a right angle bend below, shouldn't be an issue. However if it has another straight coupler, you could end up splitting / breaking that and giving yourself a difficult to control leak.

3. Or you could consider putting in a false floor above all the pipework. Probably a lot less bother and you won't lose all that much space.

I can access the pipework below the floor. There is no straight coupler but there is a threaded right-angle elbow at the bottom of the pipe, would this still be an issue or risk of splitting?

A false floor is a good idea but I need the full height that would be available so it's not really an option but thanks for the suggestion.
 
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1. There is a risk that the pipe might unscrew from the elbow, rather than the adaptors unscrewing from the pipe.
2. If there is enough pipe above the elbow and below the floor to secure with Stilsons, that would be OK.
3. If the pipe cam unscrewed below the floor, you could adopt a similar process to point 2 in my previous post, but use a male threaded iron into the elbow and extend through the floor in copper.
 
If you're happy you can isolate the pipework, I'd go with the above advice, #3. Undo below the floor at a suitable point, (ensuring the pipework to remain is held firm so it cannot disturb the next joint downstream), remove the existing and replace with copper to a suitable point above the floor.
 
I chickened out undoing the iron connections, in part coz my knees were giving me gyp, and opted just to remove the old stopcock as I had already loosened it. The threads in the coupler appeared clean/free of rust and by discarding the locknut and olive the replacement stopcock screwed directly into it.

The iron coupler has a shoulder in it, possibly the top end of the iron pipe from below, that the original stopcock tightened onto thus (I assume) helping to compress the sealant in the thread. I figured this should also work with the replacement stopcock and PTFE tape, which it appears to have done - least it screwed down and bottomed out on the shoulder and isn't leaking; I'll keep an eye on it and the iron pipes over the next few weeks just to make sure they aren't leaking.

By opting for this approach the existing outgoing pipe still lined up so I could simple reconnect it then add the scale & pressure reducers.

The one annoying thing is that when I lifted the floor to check for leaks on the old iron pipes I found that there was a straight coupler hiding under the insulation just below the floor after all. If I had seen this I could have done a better job by moving the pipe, where it comes through the floor, nearer to the side wall (as suggested above) and made even more space. Maybe I'll move the pipe closer to the side wall when and if the other pipework is altered. I also want to replace the iron pipe supplying the property because it is shedding rust into the water but that's also a job for another day- knees permitting.

The electrical bonding safety label has been remove for picture clarity and is now back in place - I'm a retired sparks for my troubles.

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