Draining gasoline from a lawn mower is a necessary task when preparing the machine for storage, performing maintenance, or replacing stale fuel. To drain the gas, prepare a siphon pump, a drain pan, and safety gear such as gloves and goggles. Run the mower until it stalls to burn fuel in the carburetor, then use the siphon to remove the remaining gas from the tank. Alternatively, disconnect the fuel line to drain into the pan. Dispose of old fuel at a certified hazardous waste facility.
Tools and Safety Preparation
Before you begin draining gasoline from your lawn mower, gather the necessary tools and take proper safety precautions. Gasoline is highly flammable, so working carefully is essential to prevent accidents and injuries.
The primary tool you will need is a siphon pump, which is used to remove fuel from the tank. A manual siphon pump with a hose is the most common option, but you can also use a hand-operated pump or a simple gravity siphon. You will also need a drain pan or a suitable fuel-safe container to catch the gasoline. Make sure the container is approved for fuel storage and has a tight-fitting lid.
Safety gear is important when handling gasoline. Wear safety glasses or goggles to protect your eyes from splashes, and use chemical-resistant gloves to protect your hands. It is also wise to have a fire extinguisher nearby in case of an emergency. Work in a well-ventilated area, preferably outdoors, to avoid inhaling gasoline fumes.
Before starting, make sure the mower is on a flat, level surface and the engine is cool. Never attempt to drain gasoline from a hot engine, as the fuel can ignite. Also, remove any sources of ignition from the area, including cigarettes, open flames, and sparks. Keep children and pets away from the work area.
It is also important to understand that gasoline vapors are heavier than air and can travel along the ground to distant ignition sources. This means you should never work near a pilot light, furnace, water heater, or any other device that could produce a spark or flame.
Siphoning Fuel from the Tank
Siphoning is the most common and straightforward method for removing gasoline from a lawn mower fuel tank. This method works well for most mowers and does not require disassembling any parts.
To siphon fuel from the tank, first remove the gas cap to allow air to enter the tank. Insert the siphon hose into the fuel tank, making sure it reaches the bottom where the fuel is. Place the other end of the hose into your drain pan or fuel container, which should be positioned lower than the fuel tank to allow gravity to assist the flow.
If you are using a manual siphon pump, follow the manufacturer’s instructions to create suction and start the flow of fuel. Once the fuel begins flowing, it will continue as long as the hose remains submerged and the outlet is lower than the tank. If you are using a gravity siphon, you may need to prime the hose by filling it with fuel or using a squeeze bulb to start the flow.
Allow the fuel to drain completely from the tank. You may need to tilt the mower slightly to access fuel in the corners of the tank, but be careful not to spill any gasoline. Once the tank appears empty, check by looking into the opening or using a flashlight. Remove the siphon hose and set it aside, being careful not to drip fuel.
If there is still a small amount of fuel in the tank that the siphon cannot reach, you can use a clean rag or paper towel to soak it up. Be sure to dispose of the rag properly, as it will be saturated with gasoline and is a fire hazard.
Draining via the Fuel Line or Carburetor
In some cases, siphoning may not remove all the fuel from the system, especially if there is fuel in the fuel line or carburetor. Draining these components ensures that no stale fuel remains to cause problems later.
Disconnecting the Fuel Line
To drain fuel from the fuel line, you will need to locate the fuel line, which runs from the fuel tank to the carburetor. Most mowers have a small fuel line clamp or a spring clip that holds the line in place. Use pliers to remove the clamp, then carefully pull the fuel line off the fitting.
Place the end of the fuel line into your drain pan and allow the fuel to flow out. You may need to lower the line below the level of the tank to allow gravity to drain it. Once the fuel has stopped flowing, reattach the fuel line and secure it with the clamp. Be sure to check for any cracks or damage to the fuel line while it is disconnected.
Draining the Carburetor Bowl
The carburetor bowl holds a small amount of fuel that can become stale and cause starting problems. To drain it, locate the carburetor, which is typically on the side of the engine. There is usually a small drain screw or bolt at the bottom of the carburetor bowl.
Place a small container under the carburetor to catch the fuel. Loosen the drain screw slowly, allowing the fuel to drain out. Once the bowl is empty, tighten the screw back up. Be careful not to overtighten, as this can strip the threads or damage the gasket.
Some carburetors have a drain hose attached to the bowl for this purpose. If your mower has one, simply route the hose into a container and open the drain valve to empty the bowl.
Running the Mower to Empty the System
Running the mower until it stalls is an effective way to remove fuel from the carburetor and fuel lines, leaving the system dry. This method is particularly useful before long-term storage, as it prevents stale fuel from gumming up the carburetor.
To use this method, start the mower as you normally would and let it run. The engine will continue running until it has consumed all the fuel in the carburetor and fuel lines. When the fuel runs out, the engine will sputter and eventually stall. This indicates that the fuel system is empty.
After the engine stalls, try to restart it a few times to ensure that no fuel remains in the system. This also helps to draw any residual fuel out of the carburetor. Once you are confident the system is dry, turn off the ignition and proceed with any maintenance or storage preparations.
Running the mower dry is a good practice before storing the machine for the winter or for an extended period. It helps prevent the buildup of varnish and deposits in the carburetor, which can cause starting problems when you use the mower again.
Note that this method only removes fuel from the carburetor and fuel lines, not from the fuel tank itself. You will still need to siphon or drain the fuel tank separately if you want to remove all the gasoline from the mower.
Proper Fuel Disposal
Properly disposing of old gasoline is important for both environmental and safety reasons. Gasoline should never be poured down drains, onto the ground, or into regular trash, as it can contaminate soil and water and pose a fire hazard.
The best way to dispose of old gasoline is to take it to a certified hazardous waste collection facility. Many municipalities operate household hazardous waste drop-off sites where you can bring old fuel for safe disposal. Check with your local waste management authority to find the nearest collection point and any applicable rules or fees.
Some auto parts stores and recycling centers also accept used gasoline for proper disposal. Call ahead to confirm that the facility accepts fuel and to learn about any quantity limits or packaging requirements. Store the gasoline in a sealed, approved fuel container for transport, and never mix it with other fluids.
If the gasoline is relatively fresh and not contaminated, you may be able to reuse it in another vehicle or piece of equipment. However, gasoline that has been stored for more than a few months or that has a sour smell should not be used, as it may have degraded and could damage an engine.
Always keep old gasoline out of reach of children and pets, and store it in a cool, dry place away from heat sources and open flames until you can dispose of it properly.
By following these steps, you can safely and effectively drain gasoline from your lawn mower, whether you are preparing it for storage or performing routine maintenance. Taking the time to do this properly will help keep your mower in good working condition and prevent problems caused by stale fuel.
