Club 80-90 Forums

Evening all. I've had a long, fraught day under the kitchen sink making some alterations to the plumbing before a new sink and unit goes in. Anyway, I've replaced the brass(?) stopcock that was there ('cos it didn't work) and when I finally came to switch the water back on, the compression joint (onto copper piping) at the top of the stopcock is weeping.

I've tried tightening it, I've tried adding more ptfe tape, I've tried having less ptfe tape, I've taken the thing out again to check and double-check the alignment of the joint . . . and it still continues to weep!

Very grateful for any ideas or suggestions!

Is it possible to get a stopcock that can be soldered onto copper piping, instead of compression joint? Only other thing I can think of is to remove the length of old pipe that it's on and start again with new pipe and olives (currently new olives on old copper pipe).

Cheers

Tony

Is your copper pipe of Imperial Measurements ?

if so ypu will need to buy a conversion kit from plumb base ......Failing that I would replace the copper pipe and olives as one.

Tug wrote:......Failing that I would replace the copper pipe and olives as one.

Yeah, I think that's the way to go. Pipe comes out at 15mm on the micrometer, it's in a 1980's extension on a terrace house.

Tony

Did you clean the old pipe before putting the new olive on? If you did put plenty of flux on and solder the olive onto the pipe. Check that you do not have too much pipe protuding into the body of the stopcock preventing the olive seating correctly.

This one caught me out a few weeks ago. Couldnt get a good seal. Turned out to be a small dent in the pipe right where the olive was sitting! Bliddy typical!
More draining water out the system!

Oldiebut goodie wrote: . . . put plenty of flux on and solder the olive onto the pipe. Check that you do not have too much pipe protuding into the body of the stopcock preventing the olive seating correctly.

Worth a try, cheers!

Tony

Some compression fittings ain`t up to what they used to be
Tried some cheapfix flexible tap connectors on a kitchen job and the nuts deformed when tightening up
After too much wasted time got push fit and no problems

http://www.screwfix.com/prods/11400/Plu ... Cocks-15mm" onclick="window.open(this.href);return false;

check the pipes are perfectly straight...... are there any dents in the pipe were you're putting the seal? Never had a problem with the few compression joints I've fitted. Shouldn't have to tighten till your knuckles go white

If anything I'd probably re-cut the pipe. If the pipework doesn't then fit you can get great flexible tap hoses with compression fittings on from DIY places.

DanO wrote:check the pipes are perfectly straight...... are there any dents in the pipe were you're putting the seal? Never had a problem with the few compression joints I've fitted. Shouldn't have to tighten till your knuckles go white

If anything I'd probably re-cut the pipe. If the pipework doesn't then fit you can get great flexible tap hoses with compression fittings on from DIY places.

this is usually the case...only nip the joints up,dont overtighten b4 you try the water as itll not give you any more seal..sometimes makes it worse

hi tone, try taking all the ptfe off and tightening it until it creaks no ptfe needed on a joint with an olive m8 in my experience. the olive does the sealing for you.

You should not need PTFE on the olive only on the thread, check you have not cracked the nut, it happened to me once where I over-tightened it and it had a hairline crack you could not see until I took it off again, failing that cut out a piece of the pipe and start again.

did you leve the old olive on if you did teke it of .if you cut it of dont put a cut
in the pipe .as i am a plumber i have had no probs with conp stop cocks . if you
try to solder itmake sure you clean pipe and put flux on . and no water left in pipe.
but i would put a new olive on and put some boss wite on . get it from pluming shop
put it on the new olive . good luck .

Check that there isn't a hairline crack on the brass body of the stop "cock", (vertically up the thread), I had this happen on a brass fitting once, couldn't work out why, tried everything, then fornd the crack, cheap fitting, too brittle I guess!

Good luck

Munnyella

Hi Tony,
Small hacksaw, gently cut through old olive, open up with flat screwdriver blade and remove. Clean copper with some wire wool and fit new nut & olive. smear olive with some boss white or jet blue, and nip up nut using a moderate amount of pressure. If it still weeps after this just tighten the offending nut half a turn and check again.
If you got at it like popeye you will deform the olive and it will never seal.
Hope this helps.
Andy.

Many thanks for all the help and suggestions everyone. Fingers crossed I think I've fixed this now. When I took it apart today and cut the new olive off I noticed that the copper pipe was pinched all the way round where the olive was, so I wonder if I've over-tightened it, especially with the ptfe on (after reading the comments above). I cut a section of the old pipe away, put some new pipe in and tightened it up more carefully this time!

I'm still keeping an eye on the drip tray that I've got underneath, but so far it's looking good.

Thanks again!

Tony