Best Auxiliary Fuel Tank for Generator: Top 5 Portable Generator Fuel Tanks
Answering the question, these are the best portable auxiliary fuel tanks for generators, chosen for reliability, compatibility, and ease of use. Ideal for growers, campers, home backup planners, and outdoor workers who need extra runtime without re-fueling often. The top picks vary by capacity, venting, and mounting styles to fit different generator models and use cases.
Summary table of selected products:
- Attwood 8806LP2: 6 gallon, EPA certified, built-in vacuum vent.
- Scepter 08668: 12 gallon, two-way vented cap, built-in gauge, tall profile.
- JJing Universal 5 Gallon: 5 gallon, compact, no vent valve.
- VEVOR 14.53 Gallon: 55L, long hose, visible gauge, durable HDPE.
- HaTur 5 Gallon: 5 gallon, iron with plating, Compact dimensions.
Attwood 8806LP2 6 Gallon Portable Tank
Best for: small to mid-size generators where space is limited. The Attwood tank is EPA and CARB compliant, featuring a cap with a built-in vacuum valve to avoid manual venting. This reduces handling steps and keeps venting consistent during refuel activities.
Why it’s selected: It offers regulatory compliance and a compact 6-gallon capacity, making it suitable for portable setups or mapped-out backup plans. The integrated venting system minimizes pressure issues during transport and use.
Limitations: The 6-gallon size may require more frequent fills for long-running generators on heavy loads. Ensure your generator’s intake aligns with the 6-gallon capacity and connection fittings.
Scepter 12 Gallon Portable Marine Gas Can (08668)
Best for: boaters and off-grid setups needing longer running times with ample fuel capacity. The 12-gallon design fits longer outings without frequent refueling, and its built-in gauge helps monitor fuel levels at a glance.
Why it’s selected: The two-way vented cap supports air flow during refuels and pressure release to prevent vapor buildup. It is compatible with diesel and ethanol-blended fuels, and includes a built-in fuel gauge for quick checks.
Limitations: This tank is relatively tall and may be less portable in tight storage spaces. Ensure you have adequate clearance for transport and mounting in your vehicle or vessel.
JJing Universal 5 Gallon Tank (No Vent)
Best for: generators that require a compact, lightweight tank when venting is not necessary or when the unit has its own venting system. The 5-gallon capacity is a common size for smaller portable generators.
Why it’s selected: This model offers built-in fuel gauge and grommets, and a clearly labeled mounting dimension set. It’s a pragmatic choice when a vent valve is not required by your generator’s design.
Limitations: It does not include a vent valve, so it may not suit engines that require vented fuel caps. Verify your generator’s fuel system compatibility before purchase.
VEVOR Marine Tank 14.53 Gallon
Best for: users needing a larger capacity tank with a clear fuel gauge and long hose for flexible installation on boats or large generators. The 14.53-gallon tank supports longer operation between refuels.
Why it’s selected: It includes a visible gauge and a long 9.8 ft hose for easier routing. It’s built from high-density polyethylene, designed to resist aging and corrosion, and includes a two-way vent-cap to manage vapor pressure.
Limitations: The hose length and tank size may require more storage space. It’s more suitable for stationary or semi-permanent installations rather than small, portable kits.
HaTur 5 Gallon Generator Gas Tank
Best for: smaller generators where a compact, durable iron tank is preferred. This option emphasizes sturdiness and a compact footprint for space-constrained setups.
Why it’s selected: The tank is made of iron with plating, designed for durability and rust resistance, and it fits compact dimensions for easy mounting on smaller generators.
Limitations: It may be heavier than polymer tanks and could be less compatible with some modern venting systems. Confirm mounting hole spacing and valve compatibility with your generator before purchase.
Buying Guide — Key Purchase Considerations
- Capacity needs: Choose 5–12 gallons for longer runtimes without refueling. Larger tanks suit boats or frequent power outages; smaller tanks fit portable generators with limited space.
- Vent system: Vented caps prevent pressure buildup during refueling and storage. If your generator has a built-in venting design, a non-vented tank may be acceptable.
- Material and durability: HDPE tanks resist weathering and corrosion; iron tanks offer added ruggedness but may be heavier.
- Gauge and monitoring: Built-in fuel gauges simplify monitoring. For vessels or vehicles, ensure gauges are visible and easy to read.
- Dimensions and fit: Check mounting dimensions and available space. Some tanks have tall profiles; measure clearance in your storage area or vehicle.
- Compatibility: Confirm compatibility with your generator’s fuel type (gasoline, diesel, ethanol blends) and inlet fittings (NPT sizes, hose connections).
- Transport and handling: Consider handles, weight when full, and ease of refueling to minimize spills.
FAQ
- What is an auxiliary fuel tank for a generator used for?
– It provides extra fuel capacity to extend runtime between refuels, especially useful for remote locations or during power outages. - Do all generator tanks require a vented cap?
– Not all do; some tank designs rely on the generator’s own venting system. If in doubt, choose a vented-cap model for safety and vapor management. - Is a larger tank always better?
– Not always. Consider space, weight, portability, and fuel availability. Larger tanks increase capacity but may complicate storage and transport. - Can I mix fuel types in an auxiliary tank?
– Do not mix incompatible fuels. Use tanks designed for the specific fuel type your generator uses (gasoline or diesel) to avoid damage or safety risks. - What should I check before buying a generator fuel tank?
– Check capacity, venting, material, gauge availability, mounting dimensions, and compatibility with your generator’s fuel fittings. - How do I know if a tank fits my generator?
– Compare mounting hole spacing, overall dimensions, and the tank’s inlet/outlet connections with your generator’s specifications.