How do you fix a leaky washer shut off valve?

A leaky shut off valve on your washing machine can cause a number of problems. Water leaks can damage flooring, lead to mold growth, and cause higher utility bills. Fixing a leaky washing machine shut off valve is an easy DIY project that you can tackle in less than an hour.

In this article, we’ll walk through the steps for diagnosing and fixing a leaky washer shut off valve. We’ll cover how to determine if the leak is coming from the shut off valve, what tools you’ll need, how to shut off the water supply, disassembling and inspecting the valve, replacing valve seals and washers, reassembling the valve, and turning the water back on.

By the end of this guide, you’ll know how to fully repair a leaky washing machine shut off valve and stop the water from leaking. Let’s get started!

What is a Washer Shut Off Valve?

The shut off valve is the small, brass valve located behind your washing machine that connects the machine’s water hoses to the home’s main water supply lines. It allows you to easily turn water flow on and off to the washing machine.

There are two types of shut off valves commonly used for washing machines:

Ball Valve

This type of valve uses a rotating ball inside the valve body to control water flow. When the valve handle aligns in the same direction as the pipe, it is in the open position and allows water to flow. Turning the handle 90 degrees closes the valve. Ball valves are quick and easy to operate.

Gate Valve

A gate valve uses a gate that lifts up and down inside the valve body. When the gate is raised fully, the valve is open. Pushing the gate down seals off the waterway and closes the valve. Gate valves are less convenient than ball valves since they require more turns of the handle to fully open or close.

Signs of a Leaky Washer Shut Off Valve

How can you tell if the leak is coming from the shut off valve rather than the washer hoses or internal parts of the machine? Here are the most common signs:

Water pooling around the valve itself – This indicates the leak is located at the valve connections or stem seal.

Corrosion or moisture on the valve body – Leaks can cause mineral deposits and corrosion on the metallic valve body over time.
Dripping water when the valve is shut off – If the valve is closed and water is still dripping, the leak is likely from the valve seal.
Leaking stops when valve is closed – This points to the shut off valve as the source of the leak.

Wet valve insulation – Some valves have insulation wrapping. If damp, this signals water is escaping the valve.

If you notice any of these signs, it’s a clear indication that the washing machine shut off valve needs to be replaced or repaired.

Tools and Materials Needed

Replacing the seals and washers inside a leaky shut off valve is a straightforward DIY repair. But having the right tools makes the job much easier. Here are the materials and tools you’ll need:

Tools

Adjustable wrench
Channel lock pliers
Screwdriver

Teflon tape
Rag
Flashlight

Bucket

Replacement Parts

Valve stem washer
Valve seat washer

Valve stem packing

The specific replacement parts required depend on the type and brand of shut off valve installed. Most hardware stores sell valve repair kits with a variety of sizes and materials for washers and gaskets. Bring the old washers with you to find matching pieces.

Shutting Off Water Supply

Before working on the valve, the water supply must be shut off. Locate the main shut off valve for the house and turn it to the closed position. This is usually near the front of the house or basement and has a lever or wheel handle.

Make sure all water is turned off by opening the lowest and highest faucets in the house to drain the pipes. Check that no water is coming out of the faucets once drained. It’s ideal to turn off the water supply at least 30 minutes prior to replacing the valve.

Disassembling the Valve

With the water supply shut off, start disassembling the valve:

Place a bucket under the valve to catch any water still in the line.

Use a rag or towel to sop up any leaking water from around the valve.
Loosen and disconnect the outlet tube nut from the valve using pliers or a wrench.
Loosen and remove the bonnet nut on the top of the valve stem using an adjustable wrench.

Remove the valve handle. The handle may be screwed on, friction fitted, or attached with a set screw.
Unscrew the valve stem and remove it from the valve body.
Check the condition of the valve seat washer at the base of the stem. If worn, replace it.

With the valve stem removed, you can access the internal components. Now it’s time to inspect the valve and identify any worn parts.

Inspecting the Valve

Carefully inspect each valve component and look for wear, corrosion, mineral deposits, and damage. Here’s what to look for on each part:

Valve Body

Corrosion – Brush off any light corrosion and replace heavily corroded valves

Cracks – Cracked valve bodies indicate a defective valve requiring replacement

Stem Seal

Dry, cracked, or compressed – Replace stem seal/packing
Sticky buildup – Clean stem with rag

Seat Washer

Warped, corroded or worn out – Replace seat washer
Mineral deposits – Remove buildup with cloth

Stem Washer

Flat surfaces – Indicated compression and need to replace washer

Cracks in rubber – Replace

Any signs of wear and tear indicate the part needs to be replaced with new seals for optimal sealing.

Replacing Seals and Washers

With all valve components inspected, it’s time to replace any worn out seals and washers:

Install new stem packing by wrapping it around the valve stem several times.
Place the new seat washer on the end of the valve stem.
Slide the new stem washer onto the stem, followed by the handle.

Insert the reassembled valve stem back into the valve body.
Tighten the bonnet nut and valve handle back onto the top of the stem.
Replace the outlet tube nut and reattached supply tube.

Make sure all parts are tight and properly seated inside the valve. Adding a bit of plumber’s grease can help parts move smoothly. With all new seals in place, you’re ready to re-open the water supply.

Turning On Water Supply

The final step is the easiest!

Turn the main water supply back on.

Turn on the washing machine shut off valve and check for leaks.
If leaks are observed, tighten connections or repeat valve replacement steps to ensure a proper seal.

It’s normal to see a bit of dripping as pressure resets in the lines. Allow the sink and washing machine faucets to run for a few minutes to purge any air. Verify no leaks are present. If the valve replacement was successful, all leaks should now be stopped!

Troubleshooting Leaky Shut Off Valves

After fixing a leaky washing machine shut off valve, you may still notice a small drip or seepage coming from the valve. Here are some steps to try:

Tighten the stem packing nut – This compresses the stem packing to improve the seal.
Replace the stem washer with a slightly larger size – A too-small washer can allow water to pass.

Use more plumber’s tape on threaded fittings – Leaks often come from loose threaded joints.
Replace the valve body – Hard water corrosion may mean the brass valve body needs replacement.

Persistent leaks likely indicate an issue with the valve body itself. Gate valves are also more prone to leaking after repair due to their design. Replacing the valve body with a 1/4 turn ball valve provides a quick, leak-free shutoff.

Replacing vs. Repairing Shut Off Valves

If your valve is very old or constructed of galvanized steel, replacement may be better than repairing the existing valve. Here are signs you should replace the valve:

Valve is over 10 years old
Galvanized or steel construction (instead of brass)

Cross-threading on connections
Heavily corroded or deteriorated valve body
Gate valve design (ball valves operate better)

Replacing with a 1/4 turn ball valve provides optimal performance and longevity. They are also easier to operate than gate designs.

Preventing Leaks

To minimize the chances of leaks recurring, here are some maintenance tips for your washing machine shut off valves:

Periodically inspect valve for drips and corrosion.

Replace washers and seals every 2-3 years.
Use pipe joint compound or Teflon tape on threaded joints.
Ensure valve is fully open when washing machine is in use.

Replace old galvanized or gate valves with 1/4 turn ball valves.

Catching valve leaks early is the best way to prevent water damage and necessary repairs down the road.

When to Call a Plumber

Repairing a leaky washing machine shut off valve is a common DIY project. But in some cases, it’s best to call a professional plumber:

Leak requires shutting off main home water supply
Valve replacement requires cutting into pipes
Persistent leaks return after repair attempts

Corroded or damaged valve components
No shut off valve present

Plumbers have specialized tools and materials to fully replace old valves or cut in new valves. They can also determine if leaks stem from larger issues with water pressure or pipes.

For major leaks or complex repairs, a plumber can ensure the job is done right.

FAQ

Here are answers to some frequently asked questions about fixing washing machine shut off valves:

How do I know if the shut off valve is bad?

Signs of a defective valve include leaking from the valve even when closed, corrosion and mineral buildup on the valve body, difficult to open or close the valve, and age over 10 years old.

What are shut off valve seats made of?

The sealing surface inside the valve body is called the seat. Seats are typically made of plastic, rubber, nylon, or brass. Older valves have leather seats.

Can a bad shut off valve cause washer leaks?

Yes, a malfunctioning shutoff valve can indirectly cause leaks at the washer hoses or internal tub seals by allowing water pressure spikes. Replacing a defective valve provides consistent water flow.

Why does my washing machine leak when the valve is open but not closed?

This points to a worn out or damaged stem washer. When open, water pressure flattens and deforms the washer, allowing water to pass through the valve. Replacing the stem washer resolves the issue.

Is it hard to replace a washing machine valve?

Replacing a washing machine shut off valve is generally straightforward. The hardest parts are shutting off the main home water supply and disassembling corroded valves. Patience and proper tools are key.

Conclusion

Fixing a leaky washing machine shut off valve requires disassembling the valve, replacing worn washers and seals, and re-installing the repaired valve. With the right materials and a little time, you can tackle this common DIY plumbing repair and stop annoying water leaks.

Be sure to inspect the valve body closely and replace the entire valve if severely corroded or damaged. Periodically replacing the valve seals and exercising the valve stem prevents future leaks. If you need help, don’t hesitate to call a professional plumber for assistance replacing tricky valve bodies.