The 9 Best Marine Fuel Tanks
This wiki has been updated 18 times since it was first published in October of 2018. Marine fuel tanks can be subjected to extreme environments on a daily basis, which is why you can't use just any container. The housing, valves, and fittings must all be resilient and corrosion resistant, and both portable and permanently-mounted models must also be able to stand up to constant sun exposure without becoming brittle. All of the items on this list meet those requirements. When users buy our independently chosen editorial recommendations, we may earn commissions to help fund the Wiki.
August 03, 2020:
We have a good mix of tanks in terms of capacity - from the Five Oceans 6 Gallon and the Attwood 6 Gallon, the 9-gallon Scepter 08667, the Attwood 12 Gallon and the mighty 18-gallon RDS General-Purpose, with the rest of the models available in a range of sizes – and I’ve only had to replace a couple of models, along with the Seawell 3.2 which was experiencing quality-related issues like leaks and splits.
For convenience, I was initially going to add a larger-capacity model with wheels for ease of transportation, and the Scepter USA DuraMax seemed good at first glance, and it even came with a convenient transfer pump. Upon further inspection however, it appears that the model had little quality control before shipping, with many of the tanks having cracks and/or splits. Obviously, these sorts of outboard marine fuel tanks are not made for larger boats, many of which will have inbuilt - and therefore, fixed - fuel tanks in their inboard engines.
I’m sure you know already, but fuel economy can be influenced by a lot of factors, like the weight of a boat, obviously its speed, and the motor’s HP as well as how deep it sits in the water. Boats like pontoons which have planing hulls sit higher in the water than displacement hulls, and tend to get a slightly better economy, but very broadly speaking, you should get about 1 mile to the gallon on boats that are 8 to 12 feet long.
You might find that older functional tanks are going to be worth their weight in gold in the coming years, as quite a few people feel that the new EPA regulation - which doesn’t allow venting of outboard marine tanks during transport or storage below 5 PSI – is actually creating more issues, since the built-up pressure is ultimately causing tanks to crack at their weakest points.
As a result, pretty much every new tank on the market is made from thermoplastic – commonly high-density polyethylene- which, when heated, expands to relieve pressure. However, it also means that durability is more important than ever with these models, and that high-quality forms of thermoplastic should be sought.
December 31, 2018:
First and foremost, marine fuel tanks must be able to stand up to the corrosive salt water environment where they will be used. For that reason, every item on our list is either constructed from plastic or rust-resistant aluminum to ensure they will last a long time for their intended use. After that we looked at the quality of the attached valves and fittings, and how well the gaskets seal the cap and fitting holes.