Valve for waste water systems

Black water system valves are often an overlooked component, but they are essential for the proper function and safety of your boat's toilet system. A faulty valve can cause unpleasant odors, backflow, and, in the worst cases, contamination of your fresh water supply. That's why it's crucial to choose quality replacement parts specifically designed for marine use.

We stock a variety of valve types to suit every need:

* **Full-Flow Gate Valves:** To completely shut off the flow.
* **Diverter Ball Valves:** To divert the flow to the holding tank or overboard (where permitted).
* **Electric Y-Valves:** To automate flow diversion, often used in conjunction with tank level monitoring systems.

Materials and Compatibility: The valves you find in this section are made from corrosion-resistant materials, specifically designed for the marine environment. Always verify the fitting diameter (from 25 to 38 mm) and compatibility with your existing system. If you have any doubts, please ask our team for advice.

Genuine Osculati and Whale Parts: Nautica Basile has been an official Osculati dealer since 1982. This means you can count on genuine replacement parts, tested and certified to ensure maximum reliability and durability. We also offer Whale valves, another leading brand in the marine industry.

Basile Workshop Tip

Valve maintenance is essential to prevent problems. Periodically check the condition of the seals and internal mechanisms. If you notice leaks or difficulty in operation, replace the valve immediately. A tip: always use marine-grade silicone grease to lubricate moving parts and prevent oxidation.

• Fast shipping throughout Italy.


• 2-year warranty on all products.


• Qualified technical support before and after the sale.


• Only products from official distributors.

If you also need to replace the hoses, take a look at our section dedicated to hoses and fittings for plumbing systems. You are sure to find the right part for your system.

What is the difference between a gate valve and a ball valve?

A gate valve offers a full-flow passage when open, minimizing pressure drop. A ball valve, on the other hand, has an internally bored ball that, when rotated, opens or closes the flow. Both are suitable for shutting off the flow, but a gate valve is preferable when maximum flow is required.

How do I choose the right black water valve for my system?

Consider the diameter of the hoses, the type of fluid (black water), the operating pressure, and the temperature. Also, check if you need a manual or electric valve. If in doubt, consult the product data sheet or contact us for personalized advice.

How often should I replace my black water system valves?

It depends on usage and environmental conditions. In general, it is advisable to check the valves at least once a year and replace them every 5-7 years, or sooner if you notice signs of wear or malfunction.

Can I use any valve for my black water system?

Absolutely not. Black water valves must be made of corrosion-resistant materials specifically designed for this type of fluid. Using unsuitable valves can cause sealing problems, unpleasant odors, and environmental contamination.

What is the difference between a gate valve and a ball valve?

A gate valve offers a full-flow passage when open, minimizing pressure drop. A ball valve, on the other hand, has an internally bored ball that, when rotated, opens or closes the flow. Both are suitable for shutting off the flow, but a gate valve is preferable when maximum flow is required.

How do I choose the right black water valve for my system?

Consider the diameter of the hoses, the type of fluid (black water), the operating pressure, and the temperature. Also, check if you need a manual or electric valve. If in doubt, consult the product data sheet or contact us for personalized advice.

How often should I replace my black water system valves?

It depends on usage and environmental conditions. In general, it is advisable to check the valves at least once a year and replace them every 5-7 years, or sooner if you notice signs of wear or malfunction.

Can I use any valve for my black water system?

Absolutely not. Black water valves must be made of corrosion-resistant materials specifically designed for this type of fluid. Using unsuitable valves can cause sealing problems, unpleasant odors, and environmental contamination.