How To Empty Gas From Lawn Mower

Storing your mower safely for the off-season requires you to empty the fuel tank to prevent gumming. If you’re wondering exactly how to empty gas from lawn mower, you’ve come to the right place. This simple maintenance task can save you from costly repairs and frustrating starting problems next spring.

Old gasoline left in the tank and carburetor can degrade, forming sticky varnish and gum that clogs critical components. By removing the fuel, you protect your engine and ensure a quick, easy start when the grass starts growing again. This guide will walk you through several safe and effective methods.

There are three primary ways to remove gasoline from your lawn mower. The best method for you depends on your tools, the amount of fuel, and your comfort level. Always perform this task in a well-ventilated outdoor area, away from any sparks or open flames.

Gather your supplies before you start. You will need safety glasses, gloves, a funnel, and approved fuel containers. Having a few clean rags on hand is also a good idea for any accidental spills.

Method 1: Siphon The Gasoline

Siphoning is the most common and efficient method for removing fuel. It’s ideal for a nearly full tank. You can use a manual pump siphon kit from an auto parts store or a simple length of tubing.

Steps For Manual Pump Siphoning

Place your empty fuel container on the ground, lower than the mower’s gas tank.
Insert the pump’s intake tube into the mower’s fuel tank. Make sure it reaches the bottom.
Place the outlet tube into your empty fuel container.
Pump the bulb or mechanism according to the kit’s instructions until fuel begins to flow steadily into the container.
Once the tank is empty, remove the tubes and securely seal both the mower’s tank and the fuel container.

Method 2: Use The Fuel Line Disconnect

Many modern mowers have a fuel line that runs from the tank to the carburetor. Disconnecting this line can allow you to drain the tank directly. Consult your owner’s manual first to locate the fuel line and any shut-off valves.

Locate the fuel line. It is usually a small rubber or plastic hose connected to the bottom of the gas tank.
Place your fuel container underneath the connection point. Have a rag ready.
Use pliers to loosen the hose clamp, if present, and carefully slide the hose off the tank’s outlet nipple.
Allow the fuel to drain completely into your container. You may need to tilt the mower slightly.
Reconnect the hose and tighten the clamp once draining is finished.

Method 3: Direct Drainage From The Tank

If your mower does not have an accessible fuel line or you prefer a more direct approach, you can often drain gas from the fillter neck. This works best for smaller amounts of fuel.

Tip the mower carefully onto its side, with the air filter and carburetor facing UP. This prevents oil from flooding the engine.
Position your fuel container and a funnel below the gas cap opening.
Slowly pour the gasoline out of the tank and into your container. Take your time to avoid spills.
Return the mower to its upright position and securely fasten the gas cap.

Remember to dispose of old gasoline properly at a local hazardous waste facility. Do not pour it on the ground or down a drain.

Preparing Your Mower After Emptying The Gas

Simply removing the gasoline is only part of the process. To fully protect your engine, you need to run the carburetor dry. This ensures no residual fuel is left inside to evaporate and leave deposits.

Running The Carburetor Dry

This is a crucial step that many people overlook. After you have siphoned or drained the bulk of the fuel from the tank, follow these steps.

Reconnect any fuel lines you may have disconnected.
With the fuel tank now empty, start the mower. It may take a few extra pulls.
Let the engine run until it uses all the remaining fuel in the carburetor bowl and naturally stalls. This usually takes just a minute or two.
Once the engine stops, you know the carburetor is empty. This simple step can prevent most winter storage issues.

Adding Fuel Stabilizer For Short-Term Storage

If you plan to store your mower for less than a month or so, you might choose to use a fuel stabilizer instead of emptying the tank completely. This is not recommended for long-term seasonal storage.

Add a high-quality fuel stabilizer to a full tank of fresh gasoline, following the product’s instructions.
Run the engine for 5-10 minutes to circulate the treated fuel throughout the carburetor.
Top off the tank with fresh gas to minimize air space, which can lead to condensation.

Stabilizer works by slowing the oxidation process that makes gas go bad. However, for maximum engine protection over several months, emptying the system is still the best practice.

Essential Safety Precautions

Gasoline is highly flammable and its vapors are explosive. Your safety is the most important consideration. Never take shortcuts when handling fuel.

Ventilation And Fire Safety

Always work outside, in an open area like a driveway. Do not work in a garage or shed with the door closed. Ensure there are no pilot lights, running engines, or other ignition sources nearby. Have a fire extinguisher rated for flammable liquids within reach, just in case.

Personal Protective Equipment

Wear safety glasses to protect your eyes from splashes. Use chemical-resistant gloves to keep gasoline off your skin. Gasoline can cause irritation and is easily absorbed. Avoid inhaling the fumes by keeping your face away from the tank opening.

Do not smoke or use any electronic devices near the work area. A static spark can be enough to ignite vapors.

Common Mistakes To Avoid

Even with good intentions, it’s easy to make errors during this process. Being aware of these common pitfalls will help you store your mower correctly.

Leaving Gas In Over Winter

This is the biggest mistake. Old gas will separate, lose its combustibility, and leave gummy residues. This almost guarantees a difficult or impossible start in the spring and often requires a carburetor cleaning or rebuild.

Draining The Oil Incorrectly

While you’re preparing your mower for storage, you might also change the oil. Be careful not to confuse the oil drain plug with any other parts. Always refer to your manual. Also, remember to tip the mower correctly—with the spark plug side up—to avoid oil leaking into the cylinder.

Forgetting To Disconnect The Spark Plug

Before performing any maintenance, always disconnect the spark plug wire. This prevents the engine from accidentally starting while you are working on it. It’s a fundamental safety rule that should never be skipped, even for a simple task like draining gas.

Frequently Asked Questions

How Long Can Gas Sit In A Lawn Mower?

Fresh gasoline begins to degrade in as little as 30 days. After 60-90 days, it can cause starting and performance issues. For any storage period longer than a month, you should either add stabilizer to a full tank or, better yet, empty the tank and carburetor completely.

Can I Use Old Gas In My Car?

No, you should not put old lawn mower gas into your car. Modern car engines have sensitive fuel systems and emission controls. The degraded fuel from your mower can cause knocking, clog injectors, and damage components. Dispose of old gasoline properly.

What Is The Easiest Way To Drain A Lawn Mower Fuel Tank?

For most homeowners, using a simple hand-pump siphon kit is the easiest and cleanest method. It requires minimal disassembly and allows you to control the flow of fuel directly into a container without tilting the heavy mower.

Do You Have To Drain Ethanol Gas From A Lawn Mower?

Yes, ethanol-blended fuel is particularly problematic. Ethanol attracts moisture from the air, which leads to phase separation and corrosion inside your fuel system. Draining ethanol gas is even more critical for preventing damage during storage.

How Do You Start A Lawn Mower After Winter Storage?

First, reconnect the spark plug wire if you disconnected it. Check the oil level and top it off if needed. Fill the tank with fresh, clean gasoline. Prime the engine if your model has a primer bulb, then set the choke to the “start” position. It may take a few extra pulls to get fuel flowing through the clean system.

Following these steps for how to empty gas from lawn mower will extend the life of your equipment. Proper off-season storage prevents the frustration of a non-starting engine and saves you money on repairs. Taking an hour now to do it right means you’ll be ready to mow without delay when the season returns.