Replacing main water shut-off valve
#1
03-08-15, 08:27 AM
Replacing main water shut-off valve
Hi, so the main water shut-off valve inside the house started leaking this morning - picture attached. None of the local plumbers have anything available until tomorrow, and the leak is too strong to leave unrepaired until then. Called the water company and they said they can come shut off the water from the street, but any advice on how I can go about replacing the old valve?
#2
03-08-15, 08:31 AM
Group Moderator
Had you tried to turn it off and now it's leaking ?
Is the water leaking from the stem ?
Take an adjustable wrench and try gently tightening that brass nut behind the handle.
That's an old valve soldered in 3/4" copper line. You would need to have the line turned off at the street before cutting it out. Replace it with a ball valve.
Is the water leaking from the stem ?
Take an adjustable wrench and try gently tightening that brass nut behind the handle.
That's an old valve soldered in 3/4" copper line. You would need to have the line turned off at the street before cutting it out. Replace it with a ball valve.
#3
03-08-15, 08:37 AM
You might be able to tighten the nut behind the handle to stop the leak. Since the pipe is painted, I can't tell what it is, maybe threaded galvanized steel?. In any event, you aren't going to use the same type of valve. A ball valve with a 1/4 turn on/off would probably be your best bet.
#4
03-08-15, 08:42 AM
Thanks! Yes, I tried to turn it off - and now it's leaking both when turned off and when turned on. It's leaking from the stem, I think.
So to replace with the new one, do I simply untighten the old one (after having the water shut off from the outside)?
So to replace with the new one, do I simply untighten the old one (after having the water shut off from the outside)?
#5
03-08-15, 08:46 AM
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#6
03-08-15, 08:58 AM
I just tightened the nut that's right behind the valve and the leak stopped.
Could this be a permanent solution, or should I be worried about the valve breaking or something at some point?
Also, is there a danger of over-tightening this nut?
Could this be a permanent solution, or should I be worried about the valve breaking or something at some point?
Also, is there a danger of over-tightening this nut?
#7
03-08-15, 09:09 AM
Group Moderator
Yes... that could definitely be a permanent repair.
Just turn the nut enough to stop the leak. See if the handle still turns somewhat freely.
Just turn the nut enough to stop the leak. See if the handle still turns somewhat freely.
#8
03-08-15, 09:20 AM
Yes, the handle still turns very freely.
It looks like there are still some threads visible after tightening (attached picture) - so the nut does not look to be overtightened?
Thanks again!
It looks like there are still some threads visible after tightening (attached picture) - so the nut does not look to be overtightened?
Thanks again!
#9
03-08-15, 02:19 PM
Super Moderator
Do you know where your water meter and street shutoff are? Normally you can buy a tool specific to your area that will reach down (if buried in the ground) to turn the municipal supply off. It's called a curb key in most areas. HD, Lowes, plumbing suppliers will all have these. And they prob won't cost more than $10.
To understand what that nut does...there is a fiber washer or cord (called packing) around the stem, and as you tighten the nut it compresses that washer/cord around the shaft of the handle. This seals it against any leakage when the valve is open. There is a washer at the inner end of the stem that fits against a sealing surface inside the valve. When you close it CW, it should fit tightly down and cut off flow. Since yours was leaking when closed, your washer is probably bad. It could also be a gate valve, and the sealing surfaces are worn or corroded away.
The valve should be replaced with a 1/4 turn ball valve no matter what.
Unless you have some good plumbing skills (soldering or experience with threaded galvanized pipe), I highly suggest you save your ducats for a few weeks and call a plumber to do the replacement. If you don't already have them, you'll spend more on the right tools than for the plumbers time.
To understand what that nut does...there is a fiber washer or cord (called packing) around the stem, and as you tighten the nut it compresses that washer/cord around the shaft of the handle. This seals it against any leakage when the valve is open. There is a washer at the inner end of the stem that fits against a sealing surface inside the valve. When you close it CW, it should fit tightly down and cut off flow. Since yours was leaking when closed, your washer is probably bad. It could also be a gate valve, and the sealing surfaces are worn or corroded away.
The valve should be replaced with a 1/4 turn ball valve no matter what.
Unless you have some good plumbing skills (soldering or experience with threaded galvanized pipe), I highly suggest you save your ducats for a few weeks and call a plumber to do the replacement. If you don't already have them, you'll spend more on the right tools than for the plumbers time.
#10
03-08-15, 02:55 PM
Do you know where your water meter and street shutoff are? Normally you can buy a tool specific to your area that will reach down (if buried in the ground) to turn the municipal supply off. It's called a curb key in most areas.
Also, if you should somehow mess up the valve (not sure how that could happen) and they have to dig a 8' hole to fix it some big bills are gonna exit your wallet.
This is my town, other areas of the country could be different.
