6 Best Fuel Cans for Auxiliary Boat Engines to Extend Your Range

There’s nothing quite like the feeling of pushing further offshore, only to be met with the nagging thought of your fuel gauge dipping toward "E." An auxiliary fuel can is more than just a convenience; it’s a critical piece of safety gear that transforms a potential crisis into a minor inconvenience. Choosing the right one means balancing capacity, safety, and ease of use for your specific vessel and needs.

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Choosing the Right Auxiliary Fuel Canister

Selecting an auxiliary fuel can isn’t as simple as grabbing the first red container you see at the hardware store. For marine use, you’re dealing with a dynamic environment—sun, salt, and constant motion—that demands specific features. The primary decision is between a dedicated marine tank designed to be plumbed directly to your engine and a portable can used for refilling your main tank.

A dedicated tank, like those from Scepter or Moeller, offers a seamless switch-over. You simply connect the fuel line to the auxiliary tank, and you’re running again. This is ideal for longer trips where you anticipate needing the extra fuel. A portable can, like a SureCan or Wavian, is better for topping off your main tank, which is a common scenario for smaller boats with built-in tanks but limited capacity.

Consider material and construction. Modern polyethylene tanks are durable, lightweight, and won’t rust, but they can swell and contract with temperature changes due to EPA-mandated venting systems. Steel jerry cans, on the other hand, are incredibly tough but are heavier and require care to prevent interior rust. Your choice depends on whether you prioritize low weight and modern features or bombproof durability.

Finally, think about how and where you’ll store it. A low-profile tank is more stable and less of a tripping hazard on a small deck. An upright can might fit better in a dedicated locker. Always secure your auxiliary fuel can so it can’t slide or tip, especially in rough seas.

Scepter Marine Fuel Tank: The Industry Standard

If you’ve been on a small boat with a portable tank, you’ve likely seen a Scepter. These red plastic tanks are ubiquitous for a reason: they are tough, reliable, and designed from the ground up for the marine environment. They are the workhorses of the auxiliary fuel world.

Scepter tanks feature a combination fuel gauge and cap with an integrated vent, making it easy to see your fuel level at a glance. Their molded feet provide stability, and the construction is UV-stabilized to prevent the plastic from becoming brittle after years in the sun. They come in various sizes, but the 3-gallon and 6-gallon models are the most common, offering a great balance of range extension without excessive weight.

Moeller Topside Tank: Low-Profile Portability

The Moeller Topside Tank addresses a key challenge on smaller vessels: stability. Its low, wide design gives it a much lower center of gravity than traditional upright tanks. This makes it far less likely to tip over in choppy water, a crucial safety feature.

These tanks are built for direct connection to an outboard engine and feature a mechanically vented cap and a clear, direct-reading gauge. The real advantage is how they stow. You can slide a Moeller tank under a seat or against a transom without it becoming a major obstruction. For skiffs, inflatables, and small center consoles where deck space is at a premium, the low-profile design is a game-changer.

Attwood Portable Fuel Tank: Compact & EPA-Ready

Attwood’s tanks are known for their robust build and full compliance with modern EPA and CARB (California Air Resources Board) regulations. This means they come with automatic vacuum valves and pressure relief systems built into the cap. You don’t have to remember to manually open a vent before running your engine.

The tradeoff with these modern systems is that they can be a bit finicky. The tanks are designed to handle some pressure buildup, which can cause them to swell noticeably on a hot day. While this is normal, it can be unnerving for new users. Attwood’s compact, stout design makes them a great, compliant choice for boaters who want a set-it-and-forget-it fuel system.

SureCan Gas Can: Spill-Proof Spout Technology

The SureCan isn’t a traditional marine tank; it’s a gas can, but it’s one of the best ever designed for refueling on the water. Its genius lies in its patented rotating spout and thumb-trigger release. You rest the spout in your boat’s fuel fill, press the trigger, and fuel flows out smoothly from the bottom of the can.

This design virtually eliminates the classic "glug-glug-spill" of old-school cans. When you release the trigger, the flow stops instantly. This level of control is invaluable when you’re being bounced around by waves and trying to avoid spilling gasoline into the water or all over your deck.

While you can’t connect it directly to an engine, the SureCan is arguably the safest and cleanest option for topping off a primary tank. It’s perfect for the boater who just needs to add a few gallons to get home, not run for hours on a separate tank.

No-Spill Poly Gas Can: Simple Push-Button Flow

Similar to the SureCan, the No-Spill can focuses on solving the problem of messy refueling. Instead of a thumb trigger, it uses a simple green push-button. Place the nozzle into the tank opening, press the button, and fuel flows. Release it, and it stops.

The No-Spill is incredibly intuitive and effective. Its auto-stop feature prevents overfilling, and the attached dust cap keeps the nozzle clean. It’s a straightforward, reliable design that delivers on its name. For boaters who find some of the newer EPA spouts frustrating and complex, the No-Spill’s push-button simplicity is a welcome relief.

Wavian Jerry Can: Rugged Steel Construction

For ultimate durability, nothing beats a classic steel jerry can. The Wavian is the gold standard, manufactured to military specifications with 0.9mm steel, a rust-proof internal lining, and a leak-proof bayonet closure. This is the can you can run over with a truck—it’s built for the most demanding conditions.

The all-metal construction means it won’t swell or contract like plastic cans. However, it’s significantly heavier, and you must use a high-quality spout (sold separately) to avoid spills. A Wavian can is an investment in lifetime durability, but it requires more care to prevent dings from rusting on the outside and to ensure the interior remains pristine.

This is the choice for the serious adventurer or commercial user who values bombproof reliability above all else. It’s overkill for many, but for those who need it, there is no substitute. It’s a piece of gear you buy once and trust forever.

Key Features for Marine-Grade Fuel Containers

When you’re making your final decision, look for a few key indicators of a quality, marine-ready container. Don’t compromise on these features, as they directly impact safety and usability on the water. The best choice for you will tick most, if not all, of these boxes.

A proper marine fuel container should have:

• EPA/CARB Compliance: Ensures the container meets modern emissions and safety standards with self-venting, low-permeation construction.
• UV-Stabilized Material: For plastic tanks, this prevents the sun from breaking down the material and making it brittle over time.
• Clear Fuel Gauge: A direct-read gauge is far more reliable than "guesstimating" by shaking the tank.
• Stable Footprint: Look for a low-profile design or molded feet that prevent the tank from sliding or tipping.
• Ergonomic Handles: A well-placed, comfortable handle makes carrying a full, 40-pound tank much safer and easier.

Ultimately, the best auxiliary fuel can is the one that fits your boat’s layout and your style of boating. Whether you choose a plumb-in tank for seamless operation or a spill-proof can for safe refueling, carrying extra fuel is one of the smartest preparations you can make. It buys you time, options, and peace of mind when you’re miles from the dock.