Why is a shut-off valve leaking at the handle?

Every shut-off valve has a stem that runs from the handle down into the valve body. Where the stem leaves the body, a seal keeps water in. On most valves that seal is packing, held tight by a packing nut.

NIBCO's instructions for its bronze gate valves describe how it works: "The packing is compressed in the stuffing box by a gland bushing and the packing nut drawn down against the packing by turning the nut clockwise." On NIBCO's two-piece ball valves, the packing nut sits right under the handle.

Packing wears. Every time the stem turns, it rubs against that seal. NIBCO's ball valve manual says that if stem leakage occurs, tighten packing "to compensate for wear." InterNACHI, the home inspectors' association, tells inspectors to look for water leaks that may come from "the valve stem, packing washer, and packing nut" on a main shutoff.

So a leak at the handle usually means one of three things:

• The packing nut has loosened. It was snug when installed and has backed off.
• The packing has worn. The seal is thinner than it was, so the same nut no longer squeezes it tight enough.
• The valve itself is failing. A cracked body, a corroded stem or worn internal parts can also leak near the handle. This one needs a new valve.

Start with the gentlest fix. You'll need a towel, a flashlight and an adjustable wrench. Here's the order we'd follow.

### 1. Figure out what kind of valve it is

Look at the handle:

• A round wheel or oval knob that takes several turns is a multi-turn valve, such as a gate valve or a multi-turn stop under a sink.
• A lever or short handle that moves only a quarter turn is a quarter-turn valve. BrassCraft describes its quarter-turn stops as controlling water flow "with an easy 90-degree turn of the handle."

For a longer tour of the types, see the different types of water valves.

### 2. Find the packing nut

The packing nut is the nut just below the handle, where the stem goes into the valve body. On a multi-turn valve, it's usually a separate hex nut you can see. On many ball valves, NIBCO notes the packing nut is "under handle," so it may be partly hidden by the lever.

Don't confuse it with the bigger nuts that connect the valve to the pipe or to the supply line. Tightening those won't fix a stem leak, and overdoing it can damage the connection.

### 3. Snug it a little at a time

This is where patience pays. NIBCO's ball valve manual says the packing nut "should be tightened in 1/8- to 1/4-turn increments, just enough to stop leakage," using a flat-jawed wrench. Its gate valve manual adds a warning: "Do not over tighten as excessive tightening may cause difficult operation of the valve and could cause damage to the stem or packing nut."

1. 1Dry the valve with the towel so you can see where the water appears.
2. 2Tighten the packing nut a small fraction of a turn, clockwise.
3. 3Wait and watch. Dry it again and check for fresh water after a few minutes.
4. 4Turn the handle once, open and back, to make sure it still moves freely.
5. 5If it still weeps, repeat with another small turn.

Stop as soon as the drip stops. If the handle starts to feel stiff, you've gone far enough.

### 4. Don't take it apart under pressure

It's tempting to pull the stem or add packing while the water is still on. Don't. NIBCO's gate valve manual says repacking of valves under pressure "is not a recommended practice" and calls it dangerous, "even if the valve appears to be back-seated." Any repair beyond snugging the nut starts with the water shut off upstream of the valve.

For a ball valve, the answer may be no repair at all. NIBCO says there are "no field repairable or replaceable components within the pressure vessel" of its two-piece ball valve, and warns against taking the pressure vessel apart "for any reason, including to attempt internal repairs."

Snugging the nut fixes a lot of handle leaks, but not all of them. Plan on a new valve when you see any of these:

• The nut has run out of travel. NIBCO's gate valve manual says that if the gland has run out of travel, the valve should be isolated and depressurized "for repacking or the addition of more packing." For most homeowners, that's the point where replacing a small stop makes more sense than rebuilding it.
• The leak comes back soon after you tighten it, or it drips from the valve body rather than around the stem.
• The valve won't fully close. A stop that leaks at the handle and also lets water through when it's off has two problems.
• The handle is seized. Don't force it. A stem that snaps leaves you with a worse leak and no way to turn it off.
• There's heavy corrosion or crusty mineral buildup on the body or stem.

### Stops under sinks and toilets

For multi-turn stops, parts do exist. BrassCraft sells a stem repair kit it describes as "for angle and straight style multi-turn valves." That still means shutting off water upstream first.

Often the better move is to replace the stop with a quarter-turn one. BrassCraft says its G2 quarter-turn stops use a "one-piece shut-off mechanism" that "works smoothly with no freeze-ups." Our step-by-step guide to replacing a toilet shut-off valve shows how the swap works.

### The main shutoff

A main valve that leaks at the handle is a bigger job, because replacing it means turning off the water ahead of it. In Phoenix, that is not a homeowner job at the meter. The city's plumbing tips say: "It's important for you to NOT shut your water off at the meter. This requires a special tool and you may be held responsible for any repairs to a damaged water meter." If you or your plumber can't find the house valve, the city says to call its Customer Services office and it will have a technician turn the water off at the meter.

A few habits help a valve last and keep it ready for the day you need it.

• Work your valves now and then. NIBCO says its ball valves "must be exercised from fully opened to fully closed periodically," and recommends a routine exercise program, "such as cycling at least once every 6 months." Our page on testing your main water shut-off valve walks through it.
• Open gate valves fully, but don't crank them hard. NIBCO's gate valve manual says it is "not recommended valves be tightly back-seated as line contamination over a long period of time may lock up the valve." Open it all the way, then ease off the pressure on the handle.
• Know where your main valve is. The City of Phoenix tells residents to "Know where your water shut-off valve is and test it regularly."
• Look for water under your valves. InterNACHI suggests inspectors check a main shutoff by wiping the bottom of the valve body and looking for watermarks on the floor below. A quick look under your sinks and at your main valve now and then catches a drip before it stains a cabinet.

If a stop under a sink has started leaking, see how to shut off water to a fixture so you know which valve controls what.

HQ is licensed and insured, runs 24/7 for emergencies, and gives free estimates with upfront pricing. If a valve won't stop dripping or won't turn at all, we can replace it with one that works the first time you need it.