Quarter-turn valve for marine use

Instant open/close action

The quarter-turn valve allows for quick and accurate control of onboard fluids – water, fuel, or coolant. A simple 90° turn opens or shuts the flow immediately.

Built for marine conditions

Made from corrosion-resistant materials like brass or stainless steel, these valves are ideal for harsh saltwater environments and long-term use.

Safe and easy to operate

The compact design ensures easy operation in tight spaces, providing instant shut-off for maintenance or emergencies.

When sailing, safety and reliability are non-negotiable. Too often overlooked, the boat valve is nevertheless a crucial link in the onboard plumbing system. Whether for leisure boating, marine navigation or motorboats, every valve, through-hull fitting, pump and connector plays a fundamental role in protecting the vessel, its hull, and its occupants. This page aims to introduce all types of valves, accessories and spare parts essential for the maintenance, safety and proper operation of your onboard water circuits, including renowned brands such as Guidi.

The essential role of valves on a boat: a non-negotiable safety

The valve, whether it's a ball valve, gate valve, rotary valve or equipped with a non-return system, is much more than a simple tap or stopcock: it allows you to interrupt water flow at any time in a pipe, protecting the boat from accidental water ingress. When servicing a circuit, isolation via valve avoids the need to haul out the boat, making it easier to service the engine, sinks or toilet pumps. At sea, especially in rough weather, heavy heeling or exposed anchorage, closing the valves of any outlets located below the waterline becomes essential to prevent water from backing up into the boat, especially through the through-hull fittings. Valves also prevent siphoning, which could cause water to rise into the engine or toilet system, even with a swan neck in place. Often underestimated, these small components play a truly critical role in onboard fluid management. Whether draining black water, flushing the cooling system for winterization, or keeping marine organisms out of the plumbing, valves are everywhere! On the other hand, it's important to remember that a failed through-hull or valve is no small matter: it can let in an impressive volume of water, far beyond what bilge pumps can handle. For example, a 2-inch through-hull can allow over 7,000 liters of water per hour... meaning the boat's safety—and even its buoyancy—can be quickly compromised.

The different types of marine valves

In marine plumbing, there are several types of valves, each with its own use. The most common are manual shut-off valves: they're used to easily isolate part of a circuit. Ball valves, also known as "quarter-turn" valves, are very handy: a simple lever action rotates the ball inside, opening or closing the passage — simple and effective. Then there are 2-way or 3-way valves, which allow redirection of the flow — for example, to choose whether wastewater goes to sea or into a holding tank. Non-return valves prevent backflow, while safety or anti-blocking valves are designed to withstand high pressures, especially on large vessels or in fuel systems. Solenoid valves, operated remotely from the electrical panel, offer modern, secure control while maintaining manual override in case of emergency.

The choice of material is key to product durability in a marine environment. Brass is often the most economical solution, but it does not hold up well in saltwater: it can degrade over time due to electrolysis or corrosion, so it needs to be inspected regularly. Bronze is known for its strength and remains the reference material for safety-critical or sensitive systems — especially when protected with appropriate anodes. Stainless steel is top-tier for hot water circuits or situations demanding corrosion resistance: it performs very well in harsh conditions, although it tends to be more expensive. Composites or reinforced plastics are a modern solution, corrosion-free and ideal for RIBs or pleasure boats. For each through-hull fitting, it is imperative to have a wooden plug within reach to quickly seal off any leak in an emergency, particularly at the base of the through-hull.

Installation and maintenance for long-lasting marine plumbing

To ensure the durability and safety of the onboard plumbing system, installation must follow best practices. Choosing the right valves, through-hulls and fittings should never be taken lightly: marine-grade equipment suited to your boat and each circuit (water, fuel, engine return, etc.) is the best choice. For every hose connection, it's best to use two stainless or corrosion-resistant clamps to guarantee a secure and leak-free fit, even when the boat is in motion. As for the swan neck, it's a classic for WC and sink drain lines. However, keep in mind that, although useful, it's not a foolproof safety measure on its own.

Preventive maintenance means operating the valves regularly to prevent them from getting blocked by limescale, debris or marine organisms. Frequent visual checks, especially during winterizing or before each sailing trip, help detect any signs of leaks or seepage (use absorbent paper or taste-test for fresh or salt water): don't skip a full inspection of your setup. Tapered plug valves are often overlooked, but they need to be lubricated regularly to stay easy to operate. And if a major leak occurs, don't delay immediately plug the through-hull with a wooden bung and call for help if needed. It's also worth noting that a hose rupture — even without pressure — happens more often than valve failures!

Regulations and DAM Marine expertise: your trusted partner

Regulations require that every intake or discharge located below the waterline be equipped with a valve, as specified in Article 240-2.13. DAM Marine is committed to helping you comply with these requirements by offering a catalog of over 70,000 spare parts and accessories for marine plumbing, engines and boat maintenance, shipped across France and worldwide. As a recognized specialist, DAM Marine offers valves and fittings for all systems: engine cooling, exhaust, fuel, water, propellers — compatible with major brands (Yamaha, Volvo Penta, Suzuki, Mercury, Honda, Yanmar, etc.), whether for motorboats, RIBs or recreational craft. Our rigorously selected valves in bronze, stainless steel, brass or composite offer excellent corrosion resistance, unmatched reliability and great value for money. Our experts are available to help you choose the right product, based on your system, vessel type (motorboat, sailboat, catamaran, etc.), and your budget.

Valves are essential components for the safety, longevity and peace of mind of all sailors, skippers and marine professionals. Their proper operation and regular maintenance are key to safe sailing and anchoring, whatever your boat type. Never compromise your vessel's safety: rely on DAM Marine for quality valves, fittings, through-hulls and accessories, shipped quickly from our stock. We can't say it enough: having reliable equipment is truly what lets you sail with peace of mind, year after year.