Problem stop tap.....i'm stuck !!! With Photo's as always

[k13 wjd]

right, i have a problem. let me quickly explain.

i had been getting bad water hammer, and presumed it was caused by a old vertical peice of pipe, which was capped, and hence full of air.

Last week i removed this pipe, but still had the hammer.

I found it to be the stop tap where the mains enters the house - if it isnt FULLY open, the hammer occurs.....

So, i open the tap, it leaks - from the shaft. i had planned to re-pack this valve today - by picking the hemp etc out, and re-placing....However, it seems there is compressed PTFE tape in there, which is impossible to remove, because the handle doesnt come off the shaft, hence its very difficult to get a engineers scribe ETC down the gap to remove the old stuff. i have some plumbers hemp here, which i was planning to use, as i presumed a valve of this age would be sealed with hemp, oiled/waxed etc. i beleive the valve to be circa 1950.

I put 10-15 turns of ptfe tape on the shaft, and nipped it up. Valve nearly fully open, and it has not leaked in the past 2 hrs. God damn is the valve tight though.

Now, my worry is that this valve is going to leak again, and if it does, will need to be dismantled, and either re-built, or replaced. Now, you'll see just how short the pipe is between the concrete and the valve - and if the truth be told, the pipe is bent slightly too.

I presume i'd be looking at turning the water of in my street for a day ( or night) or freezing the pipe before the valve.

any ideas/ any advice welcome.

( apart from soldering the shaft to the nut, the nut to the body, after putting in a new stopcock above it......)

 

[Gray0689]

If it's not leaking now what's the problem just leave it
Ps hemp is illegal to use on potable water fittings

 

[Billy Bob Bob]

why dont you leave that tap as it is knock the water off in the street and cut a new tap in above it

 

[k13 wjd]

If it's not leaking now what's the problem just leave it
Ps hemp is illegal to use on potable water fittings

just as well i didnt use the hemp then eh !!!

My worry is that the valve is now very very tight - and indeed my GF would be unable to shut the water off in an emergency. the nut is also done up rather tight - in fact, so tight i'm worried i round the edges of it. it seems to be rather soft brass.

Also, my understanding of that valve is : if the gate is completely closed, i should be able to remove the retaining nut, without water leaking out past the seal/shaft......

my valve leaks all the time with the nut removed......even with the valve closed....meaning i could spring a leak when i'm away on holiday for example.

Gas man : if i'm fitting a new valve above it, why do i need to cut the water off in the street ??? surely i just close the valve, and install one above it. That is a good idea though, i could seal this valve open, with the intent of never closing it.

If i was able to close the water of in the street, i would rebuild this valve properly, or replace with a new one. All likely to be old imperial fittings though.

 

[Billy Bob Bob]

you could knock the old one off and cut one in above but you have answered your own question its tight to turn, knackered etc leave well alone now its leak free and isolate in the street when you cut the new one in

 

[Scottley]

I never understand leaving the old one in place and cutting in a new one above? Why not just remove that one, pull the olive and put the new one in the same location?

 

[Billy Bob Bob]

I never understand leaving the old one in place and cutting in a new one above? Why not just remove that one, pull the olive and put the new one in the same location?

read the op first post the pipe is knackered and try pulling a 30 year old cone scottley they are very different to modern ones

 

[tamz]

I never understand leaving the old one in place and cutting in a new one above? Why not just remove that one, pull the olive and put the new one in the same location?

You will not need to "pull" the olive on that valve, it is a drifted one ie type B

 

[k13 wjd]

actually, having dismantled a very similar t-peice upstairs, it looked like the pipe had been flared, almost like a brake pipe on a car... But, i'm VERY reluctant to disturb that valve at the bottom. there is only an inch of pipe at the back before the valve, and the pipe has been bent at some point. i'd like to meet the man who put it there, and indeed the idiot that cast the pipe in concrete like that.

anyway, i have no outside stopcock, so i'd have to find the one in the street. even then i would have half a streets houses trying to empty themselves through that pipe......


Thanks for the replies so far guys.