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How to Drain a Boat Fuel Tank
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How to Drain a Boat Fuel Tank

In 2021, the sale of powerboats was booming, with a 34% increase in sales as compared to the same time last year.  Pontoon boats, wake sport boats, and jet boats have also seen double-digit increases.

You’ve had lots of fun on your new boat, hanging out with friends, exploring new areas, and maybe even fishing. But with temperatures falling, you are thinking about storing the boat for winter. One of the things you need to learn is how to drain a boat fuel tank.  

Don’t you wish you had a guide with boat fuel tank draining explained? Look no further. Keep on reading for everything you need to know about how to drain a boat fuel tank.

Why Should You Drain Your Fuel Tank?

Why should you worry about draining a boat fuel tank? There are many reasons you may want to drain a boat fuel tank.

The most important thing is to keep your boat safe. Your boat is an investment, and it’ll last you for decades if you take care of it now.

Of course, if you don’t want the hassle of getting your boat, you can have access to a boat of your choice with a Freedom Boat Club membership

Clean Your Fuel Tank

The first thing you need to know is that cleaning your boat fuel tank should be a regular part of your maintenance routine. This is even more important if your boat has been stored for long periods. A dirty fuel tank filled with sludge can result in engine problems in the long term.

The fuel in your tank will break down into chemicals over time. It will separate into additives, which will sink to the bottom of the fuel tank, creating a thick sludge. You want to make sure to clean      

Stale Fuel Tank

Boat fuel can go stale within 30 days, especially if it’s mixed with ethanol, as it is in some areas. Stale fuel will degrade and can clog the fuel system.

You can extend the life of the fuel by topping it up with some fresh fuel. It’s better to consider draining your boat fuel tank when you’re leaving your boat for long periods.

Empty Your Fuel Tank for the Winter

You will also want to empty your fuel tank for the winter when you’re putting it away in storage. This will ensure that you don’t end up with stale fuel that damages and corrodes your fuel tank.

Water in Your Fuel Tank

If there’s water in your fuel tank, then you want to make sure to drain and replace the fuel in your boat tank. Water can seriously damage your engine by washing away any lubrication. It can also cause corrosion and long-term damage.

Keeping Your Boat Safe

Boating safety is not a one-time thing, but an ongoing initiative. By draining your fuel tank, you can maintain and clean out the tank. This will keep your engine and your boat safe from damage or worse.

It’s one of the best things you can do to maintain your boat.

What Do You Need to Drain Your Fuel Tank?

We'll start this boat fuel tank draining guide with a checklist. Start by gathering everything you need to finish this task of draining your fuel tank. Once you have everything, it’ll make the whole process simpler.


You don’t want to use the equipment with bare hands. It’s greasy and hard to scrub off. You also want to protect your hands from any damaging materials.

Make sure your gloves are comfortable and fit your hands. You will be using a screwdriver and connecting hoses.

You want to be able to pick items without bulky gloves that don’t fit. If you don’t get the right size, you can end up spilling liquids, creating fire hazards, and endangering yourself.

Something as simple as the right size of gloves can make a huge difference in your safety and your experience.

Eye Protection

You don’t want to splash fuel in your eyes. If things are not connected correctly, you can end up damaging your retina or worse. Just grab simple protective eyeglasses.

If you’re going to be learning more about your boat, you’ll be needing those eyeglasses in the future.  

Face Mask

We’re all used to wearing face masks. One of the benefits of being on a boat is that you get to forget all about face masks for a few hours. This time though, you should consider wearing a face mask when you drain your fuel tank.

You don’t want to continuously smell fuel. Your first time can take a bit longer, so you want to make sure that you’re protecting yourself.

Fuel Hose

You need a fuel hose. It’s what you will use to drain the fuel from your boat. The best fuel hose is one with a 3/8th inch thickness. A 6-foot hose cut in two will allow you to drain both sides with a 3-foot hose each.

If you feel your boat can use a different size of hose, then do your research. Make sure you use the right hose that can make your life easier.

You don’t want spills because you chose the wrong size. You also don’t want to stop halfway when you realize that you have the wrong size.

Fuel Transfer Pump or Primer Bulb

You have two ways you can drain the fuel – either automatically with a fuel transfer pump or manually with a primer bulb.

A fuel transfer pump allows you to automatically pump fuel out of the engine and drain it. It connects to a power source, so you don’t have to do anything manually. Of course, it also costs more.

Make sure to watch the process and don’t just take a break away from it. You want to make sure nothing spills or breaks apart because it’s not connected properly. Stay focused and don’t get distracted.

You can rent a fuel transfer pump for cheaper whenever you need it. Ask your boat club if they have fuel transfer pumps to rent. If not, they can direct you to the best ones available.

On the other hand, you can also use a primer bulb. This requires you to manually squeeze the bulb and draw the fuel from the tank. It can take a bit of effort and time to get it all.

Hose Clamps

If you simply use a hose, you can end up with leaks and flying fuel everywhere, creating a fire hazard. To avoid this, get hose clamps. You can attach the clamp to the fuel transfer bulb or the primer bulb.


Don’t forget a screwdriver. It’s one of those simple things that’s easy to forget. Without it, you won’t be able to tighten the hose clamps.

Fuel Receptacle

You need something to drain the fuel into. This is where the fuel receptacle comes in handy.

How to Drain a Boat Fuel Tank – Steps to Take

If you have everything on this list, then you’re ready to start working. You need to find the right location where there are no distractions, and you can finish your project quickly. You don’t want to be going back and forth for equipment, which can just prolong the project.

Don’t worry if you haven’t done this before. We’re here to make things easy for you.

Using this step-by-step guide, you can drain a boat fuel in no time, save money and maintain your boat for the long term. Read on to also get boat fuel tank draining tips:

Step 1: Use Up the Gas in the Boat

You want to make sure that the boat’s tank is about 1/8th full. You can do this by turning on the boat and letting it run on water. You could always take your boat for one last round, but the idea here is to make sure the tank is not full.

You can take steps beforehand if you know you’re going to be draining your tank. Don’t fill up fully if you don’t think you’ll have to take your boat out. You don’t want to waste fuel and damage the environment in the process.

 Make sure you don’t run the fuel out completely.

Another way to run your boat on the water is by using water muffs to flush out the engine. 

Step 2: Get Your Boat Ready for Transport

Once you have your fuel level where you want, you can turn off the engine and get your boat out of the water. Place it on your trailer and take it to where you want to drain the fuel tank. This is the location that has the fuel transfer pump.

Step 4: Check Your Surrounding Area for Fire Hazards

Remember to look around and make sure there is no flammable material around. Keep fire hazards away from the area where you’ll be draining the fuel tank. You don’t want to take any chances with your safety here.

Step 5: Keep a Fire Extinguisher Around

Even if you’ve taken all the safety steps, mistakes can happen. You want to make sure you have a fire extinguisher around for those emergencies.

Step 6: Wear Protective Gear

Gas is flammable, and draining the fuel tank has its hazards. By taking these extra precautions, you can manage the danger and still take care of your boat. It’s simple – get protective gear.

This includes gloves, protective eyewear, and a face mask.

Step 7: Connect the Hose to Fuel Transfer Pump

Now, you are ready to connect one end of the host to the fuel transfer pump. Make sure you have the right connectors for your fuel transfer pump.

You can also connect your hose to the primer bulb. Slide the clamp over the hose until the clamp is close to the bulb. Tighten it with a screwdriver.

Step 8: Connect Other End of Hose to Fuel Receptacle

You need to connect the other end of the hose to the fuel receptacle. This is where all fuel will be drained into.

Step 9: Place Suction End Into Fuel Tank

Remove the fuel cap of the fuel tank. Place the suction end of the fuel hose into the fuel tank. Remember to make sure the hose is submerged in the fuel.

Step 10: Drain the Tank

Turn on your fuel transfer pump to drain your tank automatically.

On the other hand, if you’re using a primer bulb, squeeze it to move the fuel tank to the fuel receptacle. Keep doing it until all the fuel is gone.

Step 11: Put Fuel Cap Back On

Take the fuel receptacle out and close the fuel tank. You’re ready to put your boat into storage now.

Step 12: Discard the Gas Correctly

Remember to discard the gas properly. This is one of the most important steps in the process. Gas can cause a serious hazard to the environment if it’s not disposed of properly.

If you don’t know where to throw the gas, contact your boat club. They’re always a good resource to get you the information that you need. Otherwise, contact your local government authorities.

They generally have a designated place for disposals, like a recycling center, waste disposal site, auto parts store, or a fire department.

Now that you’ve drained your fuel tank, you can store it for the winter. You can start dreaming about the next season of fishing and other fun things you can do on a boat. 

Check Out More Tips on Boating

Now you know how to drain a boat fuel tank. You know why you should drain your fuel tank, tips and tricks to make the job easier and safer.

If you’re interested in learning more about your boat, check out fun articles like how to secure a boat to a dock.