When and Why to Replace Your Willow Go Duckbill Valves

Quick answer

Replace your Willow Go duckbill valves every 90 days, or sooner if you notice suction loss, reduced output, or visible wear. The Willow Go® Container Duckbill Valve Set (2-pack) makes it easy to swap in fresh valves and keep your pump performing reliably.

Duckbill valves are the small silicone parts that act as one-way gates inside your Willow Go pump. When they work properly, they let milk flow from the flange into the container while preventing it from leaking back. Over time, they stretch, soften, or develop tiny cracks—even if you can't see them—and suction drops.

If your pump feels less powerful or you're seeing less milk than usual, a worn valve is often the culprit. The good news: replacement is quick and affordable. In this guide, you'll learn how to spot the signs, when to replace, and how to do it without fuss.

Signs Your Willow Go Duckbill Valves Need Replacing

The most common symptom is a noticeable drop in suction. You might feel the pump isn't pulling as strongly, or you see milk pooling in the flange instead of moving into the container. Another sign is a backflow of milk toward your breast, which means the valve isn't sealing properly.

Visible wear also matters. Check the duckbill tip for tears, holes, or a permanently stretched opening. If the slit stays open when you squeeze the sides, it's time to replace. Some moms notice a change in the pump's sound—a whistling or hissing that wasn't there before—which can indicate an air leak.

• Loss of suction during pumping
• Milk not moving into the container
• Visible cracks, tears, or a stretched opening

How Often Should You Replace Them?

Willow recommends replacing duckbill valves every 90 days for optimal performance. Even if they look fine, the silicone can lose its elasticity over time, affecting the seal. Regular replacement helps maintain consistent output and reduces the risk of infection from worn parts.

If you pump heavily—more than three times a day—you may need to replace more often. Also replace if you notice discomfort or any signs of wear, as the supplier notes. Keeping a spare set on hand means you can swap parts without waiting for a delivery.

How to Replace Willow Go Duckbill Valves

Start by washing your hands and ensuring your parts are clean and dry. Remove the duckbill valve from the back of the container assembly—it should pull out with a gentle tug. Discard the old valve and insert the new one, pressing it firmly so it sits snugly in place.

After replacement, test the pump with a little water or your next session. You should immediately notice stronger suction and better milk flow. If not, check that the valve is seated correctly and that no other parts are loose or damaged.

• Wash and dry your hands before handling parts
• Remove the old valve with a gentle pull
• Insert the new valve securely and test the seal

Caring for Your Duckbill Valves Between Replacements

Proper cleaning extends the life of your valves. Willow Go duckbill valves are dishwasher-safe, but you can also wash them by hand with warm soapy water. Make sure they are completely dry before reassembling to prevent mold or mildew.

Avoid using sharp objects to clean the slit, as that can cause damage. Store your pump parts in a clean, dry place, and inspect the valves each time you clean them. Early detection of wear means you can replace them before they affect your pumping output.

Diagnosis: Should You Replace Your Valves Now?

• Symptom: Reduced suction or output: If you notice a drop in suction or less milk than usual, your duckbill valves may be worn. Try replacing the valves—this often resolves the issue.
• Cause: Visible wear or aging: Inspect the valve for tears, cracks, or a stretched opening. If the slit stays open, the seal is compromised. Replace immediately if any damage is visible.
• Action: Swap and test: Replace with a new Willow Go duckbill valve set, then test with water or your next session. If suction improves, you're done. If not, continue troubleshooting.
• Next step: If problems persist: Check other parts like flanges or the pump body for damage, or consult the full pump manual. If the issue remains, contact Willow support for further help.

Product Picks for Valve Replacement

• Willow Go® Container Duckbill Valve Set (2-pack): Food-grade silicone valves keep milk flowing in the right direction; dishwasher-safe; not made with BPA. A spare set ensures you always have a fresh valve on hand when you notice suction loss, minimizing downtime between sessions.
• Willow Sync Backup Parts Set: Includes backup parts designed for the Willow Sync pump; replace every 90 days for optimal output. While this set is for Willow Sync, it's a useful reminder that all Willow pumps require regular part replacement to maintain performance.

Replacing your Willow Go duckbill valves on schedule is a simple, low-cost way to keep your pump running smoothly and your output consistent. Keep a spare set handy, inspect regularly, and swap them out the moment you notice suction issues. Your pumping sessions will thank you.