How To Get Gas Out Of A Lawn Mower | Simple, Safe Steps

Many people assume draining a lawn mower’s fuel requires tipping it over or using your mouth to start a siphon. Both methods are unsafe and can cause injury or engine damage.

The right approach is simple and doesn’t need special tools. This guide walks through two safe ways to remove gas — using a siphon pump or a baster — and covers the critical safety steps you should never skip.

Why Safety Comes First

Before touching the fuel system, two precautions prevent most accidents: let the engine cool completely and disconnect the spark plug wire. Gasoline is highly flammable, and a hot engine or an accidental spark can cause a fire. Briggs & Stratton, a major small-engine manufacturer, recommends always disconnecting the spark plug and securing the wire away from the plug before any fuel work.

Working outdoors in a well-ventilated area is also essential. Gas fumes are heavier than air and can pool near the ground or in enclosed spaces, creating a fire or explosion risk. Even if you know the mower will be stored over winter, do not start draining until the engine is cold and the mower is outdoors on a level surface.

Why People Try Risky Shortcuts

When faced with a full gas tank, it’s tempting to take a shortcut. Many people think tipping the mower on its side will let the fuel run out, or they attempt to siphon gasoline by mouth the way they might with water. These methods are not recommended and come with real risks.

Common mistakes to avoid:

• Tipping the mower upside down: This can spill oil into the air filter and exhaust, causing damage and making the mower hard to start. No authoritative source endorses this method.
• Siphoning gasoline by mouth: Swallowing even a small amount of gasoline can cause chemical pneumonia or poisoning. Always use a manual siphon pump or a baster.
• Draining onto the ground or driveway: Gasoline contaminates soil and water. Always collect fuel in an approved gas can.
• Skipping the spark plug disconnect: Accidental engine starts while fuel is open can cause fires or injury. Always remove the spark plug wire before draining.
• Working near pilot lights or open flames: Gas vapors can ignite from a water heater pilot light or a nearby grill. Move the mower to an open area.

These shortcuts can lead to expensive repairs, spoiled mowing season, or serious injuries. The correct methods take only an extra few minutes and are far safer.

Method 1: Using a Siphon Pump

A manual siphon pump is the most efficient way to drain a full lawn mower tank. After letting the mower cool and disconnecting the spark plug, insert the pump’s intake hose into the fuel tank until it reaches the bottom. Place the output hose into an approved gas can that is lower than the tank’s fuel level. Pump the handle a few times to start the fuel flow.

Always work in a safe well-ventilated location. Autozone’s guide emphasizes this point in its safe well-ventilated location section. Gasoline fumes are heavier than air, so avoid low areas like a garage pit.

What’s the difference between a siphon pump and using a baster? Here’s a quick comparison:

Step-by-Step Safety Checklist

Before any draining method, run through this checklist to ensure everything is safe.

1. Let the engine cool completely. A hot muffler or cylinder can ignite gasoline vapors. Wait at least 30 minutes after last use.
2. Disconnect the spark plug wire. Pull the wire off the spark plug and secure it so it cannot accidentally touch the plug.
3. Position the mower on a level surface outdoors. Avoid grass that could catch fire; use concrete or bare dirt.
4. Have an approved gas can ready. Only use containers designed for fuel, placed on the ground to prevent static discharge.
5. Use a manual siphon pump or baster. Insert the hose or baster into the tank and transfer the fuel into the can.

After draining, write down the date on the gas can if you plan to use the fuel later. Old gas can still work in a car or generator but should be used within 30 days.

Method 2: Using a Baster or Pipette

If you don’t have a siphon pump, a large turkey baster or a pipette works well for partial tanks. The process is similar: cool the engine, remove the spark plug wire, and then insert the baster into the tank. Squeeze the bulb, release to draw fuel, then dispense into your gas can. Repeat until the tank is empty.

A baster is slower than a pump but avoids the dangerous temptation to siphon by mouth. The Village of Shorewood safety guide explicitly warns to never siphon gasoline by mouth — never siphon by mouth is a critical rule. A baster is a safe alternative, though it may not reach the bottom of a deep tank.

Here’s a quick reference table for do’s and don’ts:

The Bottom Line

Draining gas from a lawn mower doesn’t require risky methods. The two safe options — a manual siphon pump or a turkey baster — both work when you follow the same basic rules: cool engine, disconnect spark plug, work outdoors, and use approved containers. Avoid the common shortcuts like tipping the mower or siphoning by mouth.

If any step feels unclear, or if your mower has a complex fuel system, consult the owner’s manual or a small engine repair shop. They can confirm the safest way to handle your specific model and prevent costly damage.