50 Gallon Fuel Tank with Pump: A Boater's Complete Guide

If you have landed on this page, you have already done most of the thinking. You know a 50 gallon fuel tank with pump is where the portable fuel category actually gets useful, and you are trying to figure out which one deserves your money. This guide walks through why 50 gallons is the right size for most serious boaters, what to look for in the tank and pump combination, and how the Smart Ass Fuel Mule® handles the category better than anything else available.

Why 50 Gallons Is the Right Size

Smaller portable fuel tanks look attractive on price. They also disappoint most owners within the first month. A 25 or 30 gallon tank means two gas station trips per fueling weekend and two loading and unloading cycles. The caddy gets used less, because the process feels like more trouble than it is worth.

A 50 gallon fuel tank with pump changes the math completely. One gas station trip commonly refuels a full wake boat. A multi-watercraft household refuels in one cycle. And the more often you are on the water, the faster it pays for itself. Fuel every weekend in season and that is a lot of gas station runs you stop making. And the caddy actually stays in your workflow, because the effort-to-payoff ratio finally makes sense.

Boaters end up buying a 50 gallon fuel tank with pump for a handful of reasons that usually stack together.

• Marina markup: $2 to $3 or more per gallon extra adds up fast across a season.
• Time savings: fueling at home on your schedule beats waiting in line at the fuel dock on a Saturday morning.
• No fuel dock: many inland lakes have no fuel dock at all.
• Premium gas availability: premium for supercharged wake boats and other high-performance engines can be hit-or-miss at marinas even when regular unleaded is available.
• Diesel availability: often only one marina per lake carries diesel, if any.

Any one of those reasons is enough to justify the purchase. Most owners have two or three.

What Fits Different Boats

Wake Boats and Ski Boats

A wake boat pulling wakeboarders or skiers burns somewhere around 5 to 8 gallons per hour at tow speed. Wakesurfing with heavy ballast is the thirsty end, commonly 10 to 14 gallons per hour, because the engine is working hard against all that weight and drag. Do the math on an afternoon of surfing and it adds up fast. Get out with a decent sized group of six or eight and everybody takes a set, and a full 50 gallons can be gone in a single day. A 50 gallon fuel tank with pump covers that in one fill, or stretches across two days if you plan it right.

Pontoons

Pontoon burn depends mostly on what is hanging on the back. A modest 90 to 150 HP pontoon burns around 4 to 6 gallons per hour cruising. A big tritoon with 200 HP or more pulling tubers can burn 8 to 15 gallons per hour or more at speed. Pontoon families also tend to stay out longer. Even a leisurely afternoon of cruising at 5 gallons per hour adds up to 20 gallons or so, and a tritoon pulling tubers all day pushes well past that. One fill of a 50 gallon caddy covers a full day with room to spare.

Fishing Boats

Fishing boats are the widest category of all, from a jon boat with a tiller outboard to a big center console with twins, so there is no single number. A rough rule of thumb for gasoline outboards is about one gallon per hour for every 10 horsepower at wide open throttle. So a 150 burns around 15 gallons per hour flat out, and a lot less idling between spots. A bass boat that spends its day idling and running between spots often averages around 4 gallons per hour. A small center console cruising efficiently can get by on 3 to 5 gallons per hour, and a bigger boat with twins climbs fast from there. A 50 gallon caddy handles a full day of fishing plus a top-off for the next morning without a station trip.

Multi-Watercraft Households

Households with multiple watercraft see the biggest benefit. A wake boat plus two PWCs can run through most of a 50 gallon caddy in a single busy Saturday if everyone is on the water. One fill covers it, which turns fueling from a scheduling problem into a non-event. And if that describes every weekend at your place, the 70 gallon version below is worth a hard look.

What to Look For in a 50 Gallon Fuel Tank with Pump

Not every 50 gallon fuel tank with pump is built for real use. The difference that matters most is whether the thing can actually get itself to your boat. That means across grass and gravel, down a hill, up a ramp, and in and out of a truck bed. All of that with several hundred pounds of fuel on board, and brakes to hold it. Nobody but Smart Ass Products builds a motorized fuel caddy that does that. After mobility, the tank material, the pump specs, and the safety features decide whether it lasts.

Mobility: Off-Road, Ramps, and Hills

A full 50 gallon caddy easily weighs 450 to 500+ pounds. That is over 300 pounds of gasoline plus a tank and chassis stout enough to carry it. No traditional caddy is designed to safely handle that kind of load, particularly over rough or uneven terrain. And you can forget about loading it in and out of a truck when it is full. Hard plastic casters catch on dock boards and follow the path of least resistance instead of tracking where you point them. Traditional caddies have no brakes, period, which means a loaded caddy can roll away from you on any incline at all. That is a problem you never want to have, ever.

A traditional caddy at that size needs two people to move safely, even on level concrete. And if you ever need to load it in a truck, you are looking at an elaborate ramp and winch setup. This is exactly where the Smart Ass Fuel Mule® shines. Nobody else makes a motorized fuel caddy that climbs hills, handles off-road terrain, and goes up and down ramps under its own power with hydraulic brakes to hold it.

Tank Material

DOT-approved 3003 aluminum with internal baffles is the marine standard. Aluminum resists corrosion, holds up against non-ethanol and ethanol-blended fuels, andthe baffles prevent violent fuel slosh when you transport the tank over rough ground. Polyethylene tanks are cheaper but degrade in UV. Uncoated steel is a poor choice, period. Coated steel is better, but that depends on the coating's longevity and how well it is cared for. It will degrade in time once it is exposed to the elements.

Pump Quality and Speed

A budget pump rated at maybe 8 GPM on a 50 gallon tank means a six minute transfer at best, and usually longer. A 15 GPM pump on the same tank cuts that to under four minutes. UL-listed auto-shutoff nozzles are a safety layer worth paying for, because overfilling is the single biggest spill risk you face at the dock. Even with auto-shutoff, the right practice is to stay with the nozzle while it dispenses. Sit and enjoy a cold drink. The auto-shutoff is a safety feature, not permission to walk away.

Battery Type

If the pump is electric, the battery chemistry matters more than most buyers realize. Sealed lead acid (SLA) batteries are the safe choice for a fuel environment. Lithium-ion cells can catch fire when damaged and get wet, and once they light they do not go out easily at all. In a fuel context, that is a genuine deal-breaker. Any 50 gallon fuel tank with pump worth owning should use SLA (or an equivalently safe chemistry like LiFePO4).

The Smart Ass Fuel Mule® 50 Gallon

The Smart Ass Fuel Mule® is the only self-propelled motorized 50 gallon fuel tank with pump on the market. A patented design with no competitor or alternative.On-board electric drive with a thumb throttle, plus hydraulic disc brakes with a parking brake, solve the mobility problem completely. Off-road wheels handle real dock and lakefront terrain. The operator just steers.

The pump is a 15 GPM GPI electric unit with a UL-listed auto-shutoff nozzle and 10 feet of antistatic hose.That flow rate beats every legal street fuel pump in the United States (federal regulation caps street pumps at 10 GPM). It is also faster than most marina pumps. A full 50 gallon transfer typically takes about 4 minutes.

The tank is DOT-approved 3003 aluminum with internal baffles, vented at 2.5 psi, and compatible with non-ethanol gasoline, E10, E15, diesel, kerosene, AVGAS, and Jet A. Power comes from a pair of 12V 20Ah sealed lead acid batteries wired in series for a 24V DC system, specifically for fire safety. Built in the USA in Gainesville, Georgia using UL and DOT approved components.Intertek, a leading Nationally Recognized Testing Laboratory, carefully reviews the design for safe use and operation. Rated for slopes up to 15 degrees continuous travel and 22 degrees on ramps. And yes, it comes with a warranty.

The Smart Ass Fuel Mule® is also built using aluminum tanks manufactured by ATI (Aluminum Tank Industries) under DOT Special Permit SP-14227. That permit specifically allows filling and dispensing while in the pickup truck bed. That is a meaningful practical difference from traditional fuel caddies, which typically require unloading before fueling because static charge cannot dissipate safely in a truck bed.

When 70 Gallons Makes More Sense

The Smart Ass Fuel Mule® comes in a 70 gallon Flatlander version that is worth considering for households that regularly fuel multiple watercraft or want more range between fill-ups.

A wake boat plus two PWCs plus a top-off for a fishing boat all come out of one caddy fill. The Flatlander shares almost every spec with the 50 gallon version (same 15 GPM pump, same auto-shutoff nozzle, same SLA batteries, same off-road wheels and hydraulic brakes). The tank is the same DOT-approved 3003 aluminum construction built under the same DOT Special Permit, just taller. It runs about 6.25 inches taller than the 50 gallon tank, with every other dimension identical. The ramp rating is derated for the added weight.

With a full tank, it is rated for 15 degrees on ramps and 10 degrees continuous travel. That compares to 22 and 15 for the 50 gallon (just use longer ramps if it is full). It is still very capable on moderate off-road terrain, just with a bit lower threshold for the extreme stuff. At 30 inches wide it fits through a standard doorway, same as the 50 gallon. If your dock access is reasonable and you fuel multiple boats, the Flatlander is often the better long-term choice.

Frequently Asked Questions

How long does a 50 gallon fill actually last?

Depends on the boat. A wake boat running heavy ballast for a group all afternoon can burn a full 50 gallon fill in a single day. Pontoons and fishing boats stretch it across two or three outings. Multi-watercraft households often drain a 50 gallon fill in one busy weekend.

Do I need an electric pump, or will a hand-crank work on a 50 gallon tank?

For 50 gallons, electric is the right answer. Cranking a manual pump for the fifteen to twenty-five minutes it takes to transfer 50 gallons is a workout. You will regret it by your second fill, and I mean CONTINUOUS cranking. You stop, the flow stops. Electric pump caddies can also be had with auto-shutoff nozzles, which hand-crank caddies generally cannot.

How much does a full 50 gallon fuel tank weigh?

North of 450 pounds for anything built to carry it, and a full 50 gallon Smart Ass Fuel Mule® comes in at about 530 pounds. Fifty gallons of gasoline is over 300 pounds on its own, plus the weight of the tank, pump, frame, and battery system. That is not weight you safely move by hand. It is why the Smart Ass Fuel Mule® drives itself, with an electric motor and hydraulic brakes. That is what makes moving that much fuel over and around obstacles and across rough terrain near effortless. You steer. It does the work.

What is the difference between the 50-gallon and 70-gallon Smart Ass Fuel Mule®?

Capacity and terrain capability. The 50-gallon is the heavier-duty off-road option, rated for ramps up to 22 degrees. The 70-gallon Flatlander gives you more range between fills. It is rated for 15 degrees on ramps and 10 degrees continuous travel with a full tank. It is designed for boaters who need capacity but not quite as extreme off-road capability. They are still very capable on moderate off-road terrain, just with a bit lower threshold for the extreme stuff.

Can I transport 50 gallons of gasoline legally?

Yes. Under U.S. federal regulations, up to 119 gallons is fully legal in DOT-approved containers. Most states match federal rules, but check your state and local regulations to confirm they do before you load up.

Can I fill the Smart Ass Fuel Mule® while it is strapped in my truck bed?

Yes. The tanks the Smart Ass Fuel Mule® is built with are manufactured under DOT Special Permit SP-14227. That permit specifically allows filling and dispensing while the tank is in the pickup bed.

Making the Call

You own a runabout, wake boat, ski boat, pontoon, cruiser, or center console with any real fuel appetite. For that boat, a 50 gallon fuel tank with pump is where the portable fuel category stops feeling like a compromise. It commonly covers a real weekend of fueling in one trip. It stays in the workflow because the process is genuinely easier than driving to the marina.

The Smart Ass Fuel Mule® is the only 50 gallon tank in the category that solves the mobility problem completely. That is the difference between a caddy that gets used every weekend and one that gets abandoned by August. If your setup calls for more capacity, the 70 gallon Flatlander is the same design with more range.

If you want the full spec sheet, video walkthroughs from real owners, and current pricing on both versions, the Smart Ass Fuel Mule® product page has all of it.