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Spring is here, and it's time to get your restroom trailer ready for the busy season ahead. After a long winter in storage, it's important to give your unit a thorough check—and one of the most overlooked components is the metering cartridge inside your faucet. If ignored, a worn or damaged cartridge can lead to leaks or inconsistent water flow. In this guide, we’ll walk you through exactly how to inspect and replace it, so your restroom trailer is functioning flawlessly from day one.

Step 1: Gather Your Tools

Before you begin, make sure you have the following:

• A clean rag
• A crescent wrench or channel lock pliers
• (Optional) WD-40 for cleaning and lubricating the spring

Step 2: Locate the Metering Cartridge

You’ll see a nut located on each metered faucet—this is the piece you’ll need to loosen to access the metering cartridge.

Step 3: Protect Your Faucet

To avoid scratching the metal surface, wrap your rag around the nut before applying any tools. This extra step keeps your faucet looking new.

Step 4: Loosen the Faucet Nut

Using your wrench or pliers (placed on top of the rag), gently loosen the nut on the faucet. It should unscrew fairly easily. Once loose, lift the top part of the faucet off to expose the metering cartridge inside.

Step 5: Remove the Metering Cartridge

Now that the faucet top is removed, you’ll see the metering cartridge—it looks similar to a spark plug. Gently wiggle it free and pull it out.

Step 6: Inspect the Cartridge

Give the cartridge a thorough visual inspection. You’re looking for:

• Any cracks in the plastic body
• Broken or deteriorated O-rings (the two black rings around the cartridge)

If you see any damage, it’s time to replace the cartridge. A faulty one can cause leaks or water to spray from the faucet unexpectedly.

Step 7: Clean and Adjust the Spring

While the cartridge is out, you’ll notice a spring inside the faucet housing—this is the timing spring. Spray it lightly with WD-40 to prevent it from sticking. If needed, adjust the spring tension to adjust the faucet shut-off timing.

Step 8: Reinstall the Cartridge

Slide the cartridge back into place, making sure it sits snugly in the faucet.

Step 9: Reattach the Faucet

Place the top portion of the faucet back over the cartridge and screw the nut back on by hand until it’s finger-tight.

Step 10: Tighten with Care

Wrap your rag around the nut again, give it a gentle squeeze with your wrench or pliers, and add a small additional turn—about six inches of rotation—to secure it in place without over-tightening.

Ready for the Season

By following these simple steps, you’ll ensure your restroom trailer’s faucet system is clean, leak-free, and ready to handle guests. Regular maintenance like this not only keeps your trailer performing at its best but also prevents small issues from becoming costly repairs down the line.

If you run into any questions or need replacement parts, don’t hesitate to reach out to us. We're always here to help!