A Step-By-Step Guide To Filling Your Boat With Gas

Refuelling a boat is a simple process, but it requires more caution than refuelling a car. Before you start, ensure your boat is secured to the dock, the engine is off, and all passengers have disembarked. The type of fuel you need will depend on your engine. Most small boats and pontoons run on gasoline and ethanol, but larger boats may require diesel. If you have a 4-stroke gasoline engine, non-ethanol fuel is perfect. If it's a 2-stroke engine, you'll need to mix non-ethanol fuel with 2-stroke oil. For diesel engines, it's best to hire a diesel mechanic.

Safety precautions: sniff tests, no smoking, no open flames, no sparks

Filling a boat with gas is more complicated than filling a car or truck, and there are many simple but potentially life-saving safety precautions to be aware of. Here are some essential safety precautions to take when fuelling a boat, with a focus on sniff tests, no smoking, no open flames, and no sparks:

Sniff Tests

Before starting the engine, it is important to check for any fuel vapours or fumes that may have escaped. Take a sniff to detect any fumes, and if any are present, increase air circulation and wait until they have fully dissipated before turning on the engine. If you have an inboard gasoline engine, turning on the blower for four minutes is crucial to removing any lingering fumes in the bilge.

No Smoking

It is imperative that no one smokes in the area while fuelling a boat. This precaution is crucial to minimising the risk of a fire. All flames, including grills and cigarettes, must be extinguished.

No Open Flames

Any open flames, including grills, must be put out before fuelling a boat. This is a critical step in fire prevention.

No Sparks

To prevent static sparks, keep the nozzle of the fuel pump hose in solid contact with the tank opening during fuelling. Additionally, ensure that all electrical equipment is turned off, as it could generate sparks.

• Secure the boat to the fuelling dock or gas station pump.
• Ask all passengers to disembark for stability and safety.
• Shut off the engine.
• Close all doors, windows, and hatches to prevent fumes from entering and accumulating in enclosed spaces.
• Avoid filling the tank to the brim. Leave room for fuel expansion.
• Wipe up any spilled fuel with absorbent pads and dispose of them properly.
• Let fumes dissipate before starting the engine, and open all hatches and ports to allow ventilation.

Choosing the right fuel: check owner's manual, avoid ethanol, consider octane level

Choosing the right fuel for your boat is essential for reliable and optimal performance on the water. Using the wrong type of fuel can cause severe issues with your boat's engine, including seized internal components and clogged fuel lines, injectors, and filters.

To ensure you are using the right fuel, the first thing you should do is check your owner's manual. The manual will provide guidance on the fuel and oil requirements for your specific engine. It will also help you comply with the manufacturer's warranty requirements. If you do not have a physical copy of the manual, you can check online or order one from a dealer.

When it comes to ethanol in boat fuel, it is generally recommended to avoid it if possible. Ethanol can absorb moisture from the marine environment through the fuel tank vent system, which can lead to phase separation. This can cause water to settle at the bottom of the tank and potentially damage the engine. Additionally, ethanol has corrosive effects on the fuel system components, and its solvent properties can quickly corrode rubber and fiberglass.

The maximum amount of ethanol that can be safely used in marine engines is 10%, often referred to as E10 fuel. Using fuel with a higher ethanol content, such as E15 or E85, can void the warranty and cause irreversible damage to the engine. However, if you are using E10 fuel, it is important to add a high-quality fuel additive to protect your engine from the potential negative effects of ethanol.

When choosing the right fuel, you should also consider the octane level. The owner's manual may specify a minimum fuel octane rating. Some high-performance engines may require a higher octane rating than "regular" 87 octane. For example, REC-90 is an ethanol-free, 90-octane unleaded gasoline blend designed for marine and small engines that can be damaged by ethanol. It is important to note that ethanol-free gasoline is more expensive and may require a thorough cleaning of fuel tanks and lines if switching from other fuel types.

Refueling process: secure boat, open fuel cap, insert nozzle, control flow

Refueling a boat is a simple process but requires caution to avoid damaging the boat or the surrounding ecosystem. Before you begin, ensure you are using the right type of fuel for your boat. Check the owner's manual for the exact type of fuel your boat needs, as using the wrong fuel can damage the engine.

Secure the Boat

First, make sure your boat is securely tied to the dock. Shut down the engine(s) and extinguish all open flames. Turn off all electronics, including the ignition, to avoid sparks that could ignite gasoline vapours. If your boat has a cabin, close all doors and hatches to prevent fumes from filling the enclosed spaces. Ask your crew and guests to disembark and enjoy the view while you refuel.

Open the Fuel Cap

Double-check that your dock lines are secure, then open the fuel fill cap. Modern boats usually have well-marked fuel fills, but be careful not to mistake the fuel fill for the water tank or another compartment.

Insert the Nozzle

Place the fuel pump nozzle into the fuel fill hole.

Control the Flow

Pull and hold the trigger mechanism to start the fuel flow. Keep a firm grip on the nozzle and gradually increase the pressure to speed up the flow. If fuel starts to gurgle or splash out of the fill, reduce the pressure and adjust the nozzle. Stop pumping before the tank is completely full to prevent overflow and fuel entering the water. When the tank is almost full, you may hear gurgling or observe fuel spitting out of the tank's vent. These are signs that the tank is nearly full, and continuing to pump may cause an overflow.

Once you have finished refueling, replace and tighten the fuel fill cap. If your boat is a stern drive or inboard with a blower, run it for at least four minutes before starting the engine. You can also do a "sniff test" by smelling the bilge and cabin to ensure no fumes are collected there.

Stopping at the right time: listen for gurgling, avoid overflow, wipe spills

Stopping at the right time is crucial when fuelling a boat. It is important to prevent overflow and spills, as these can be dangerous and harmful to the environment.

Firstly, listen out for gurgling sounds. On some boats, this may indicate that the tank is almost full. If you hear gurgling, reduce the pressure on the trigger and adjust the nozzle to see if you can get a better flow. If gurgling continues, this is a sign that the tank is full and you should stop pumping fuel immediately.

If at any point fuel begins to overflow or spit out of the tank's vent, stop filling the tank right away. Remove the pump nozzle and replace the fuel fill cap.

It is important to avoid topping off the tank, as this can lead to overflow. Always leave some space in the tank and do not try to completely fill it.

If a spill occurs, it is important to wipe it up immediately. Keep an absorbent cloth or a fuel diaper handy to wipe up any spills. Dispose of the cloth properly on land. By law, any fuel spill that leaves a sheen on the water must be reported to the U.S. Coast Guard via the National Response Center.

After refueling: ventilate, sniff test, run blower, check bilge

After refuelling your boat, there are several important steps to take to ensure the safety of yourself and your passengers.

Firstly, it is imperative to ventilate the boat. Open all windows, ports, doors, and other openings to allow fresh air to circulate. This will help to prevent the build-up of flammable fuel vapours, which can pose a serious risk of explosion.

Next, perform a "sniff test" by smelling the bilge and engine compartment for any remaining fuel vapours. This is an important safety measure, as fuel vapours settling in enclosed areas could potentially explode if not properly ventilated. If you can still smell fuel vapours, continue ventilating until they have dissipated.

If your boat is equipped with a power ventilation system (exhaust blower), now is the time to use it. Turn on the blower for at least four minutes before starting your engine. This will help to eliminate any remaining fuel vapours in the bilge.

Finally, check the bilge for any signs of fuel spills or leaks. If there is fuel in the bilge, it will continue to emit flammable vapours, even after ventilating. In this case, clear the fuel from the bilge and leave the blower running until the strong odour of gasoline has disappeared.

By following these steps, you can ensure that your boat is properly ventilated and safe to operate after refuelling.

Frequently asked questions