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willgg
Leaky main shut-off valve

I inherited an old house. Main shut off is leaking by slightly. Any ideas on how to repair this without having the city come to shut off the outside main? The valve is an old style gate valve with packing nut. I've thought about putting a newer valve further in on the line. The problem is, the plumbing is so old that I am afraid of breaking pipes. P.S.- Total replacement of all pipes is not an option which I want to take on. Too expensive.

Fencepost
Re: Leaky main shut-off valve

If your meter is accessible, there should be a shutoff valve just upstream of it. You should be able to give this 1/4 turn clockwise to shut off the water. Usually, this valve doesn't have much of a handle; if you use pliers or a wrench you'll probably skin your knuckles and exclaim loudly. The proper tool for the job is called a "meter key".

By leaking, do you mean that it's dripping and getting the surroundings wet, or that you shut it off and it doesn't shut off completely?

How you replace the valve depends on the type of pipe you have. If it's galvanized steel, cut out the valve and about 6" of pipe on each side using a tubing cutter or hacksaw. Get a ball valve the right size and two nipples, sized so that when threaded into the ball valve the whole assembly is around 1/2" shorter than what you cut out. Get two compression couplings sized for that pipe, and use them to install the replacement valve. Make sure that the existing pipe is clean & not rusty. If it's rusty, you may need to sand it with emery cloth so it's smooth.

If it's copper pipe, you can do something similar to the above, but do not mix copper & galvanized steel pipe or fittings. That's a recipe for leaks. It's OK to mix steel pipe and brass/bronze fittings.

The best way to do this with copper pipe is do something similar to the above, but instead of using compression couplings, solder the new pipes & valve in using copper repair couplings. Look online for instructions for soldering copper pipes, and practice on a couple of scrap pieces before doing it for real.

willgg
Re: Leaky main shut-off valve

I meant that the valve doesn't completely shut off. Water still leaks by.

canuk
Re: Leaky main shut-off valve

If it's the main shutoff valve for the inside of the home ..... there's not much you can do other than having the water shut off outside to the home.
Definately replace the gate valve with a ball valve .... they're much better.

murphmgh
Re: Leaky main shut-off valve

you need to replace tis valve,if you try to "crank" it closed you stand a very good chance of this valve breaking in the off position and you will have to have the city shut it off from the street,,thus incurring possibly higher charges for the emergency call out

[email protected]
Re: Leaky main shut-off valve
Fencepost wrote:

If your meter is accessible, there should be a shutoff valve just upstream of it. You should be able to give this 1/4 turn clockwise to shut off the water. Usually, this valve doesn't have much of a handle; if you use pliers or a wrench you'll probably skin your knuckles and exclaim loudly. The proper tool for the job is called a "meter key".

By leaking, do you mean that it's dripping and getting the surroundings wet, or that you shut it off and it doesn't shut off completely?

How you replace the valve depends on the type of pipe you have. If it's galvanized steel, cut out the valve and about 6" of pipe on each side using a tubing cutter or hacksaw. Get a ball valve the right size and two nipples, sized so that when threaded into the ball valve the whole assembly is around 1/2" shorter than what you cut out. Get two compression couplings sized for that pipe, and use them to install the replacement valve. Make sure that the existing pipe is clean & not rusty. If it's rusty, you may need to sand it with emery cloth so it's smooth.

If it's copper pipe, you can do something similar to the above, but do not mix copper & galvanized steel pipe or fittings. That's a recipe for leaks. It's OK to mix steel pipe and brass/bronze fittings.

The best way to do this with copper pipe is do something similar to the above, but instead of using compression couplings, solder the new pipes & valve in using copper repair couplings. Look online for instructions for soldering copper pipes, and practice on a couple of scrap pieces before doing it for real.

after cutting off the valve, do you have to rethread the pipe to use the compression couplings? if so, what do i need to do?

Paul the plumber
Re: Leaky main shut-off valve

the only other solution you have is to freeze the pipe behind tho old shut off valve ,there is a tool for that wich most plumbers have ,then you can sweat on a quarter turn ball valve

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