Leaving gas in your lawn mower over the off-season is a question that sparks debate among homeowners. The answer isn’t a simple yes or no. Several factors influence the decision, impacting the lifespan and performance of your machine. Understanding the potential consequences of both approaches will empower you to make the best choice for your specific circumstances. This comprehensive guide dives deep into the world of lawn mower fuel, offering insights to keep your mower running smoothly for years to come.
The Perils of Leaving Gas in Your Lawn Mower
Leaving gasoline in your lawn mower’s fuel tank for extended periods, especially during the off-season, can lead to a host of problems. Gasoline isn’t as stable as you might think. Its composition changes over time, leading to various issues that can affect your lawn mower’s performance.
Gasoline Degradation and Stale Fuel
One of the primary concerns is gasoline degradation. Gasoline is a complex mixture of hydrocarbons, and over time, these components break down. This process is accelerated by exposure to air and fluctuating temperatures. Stale fuel loses its combustibility, making it difficult to start your lawn mower.
The more volatile components in gasoline evaporate first, leaving behind heavier, less combustible residues. This changes the fuel’s octane rating and can lead to engine knocking or pinging.
Gum and Varnish Formation
As gasoline degrades, it can form gum and varnish deposits. These sticky substances can clog the carburetor, fuel lines, and fuel filter. A clogged carburetor is a common cause of lawn mower starting problems. These deposits restrict fuel flow, leading to poor engine performance, rough idling, and even complete engine failure.
Removing these deposits can be a tedious and costly process, often requiring professional servicing. Prevention is always better (and cheaper!) than cure.
Water Absorption and Corrosion
Gasoline is hygroscopic, meaning it absorbs moisture from the air. This is especially problematic in humid environments. Water in the fuel tank can lead to corrosion of metal components, particularly in the fuel system. Rust and corrosion can damage the fuel tank, fuel lines, carburetor, and other vital parts, leading to expensive repairs.
Water can also separate from the gasoline and settle at the bottom of the fuel tank, potentially freezing during cold weather and causing further damage.
Ethanol’s Role in the Problem
Many modern gasoline blends contain ethanol. While ethanol is intended to improve octane and reduce emissions, it also exacerbates some of the problems associated with leaving gas in a lawn mower. Ethanol attracts water more readily than gasoline alone, increasing the risk of corrosion and phase separation.
Phase separation occurs when the ethanol and water separate from the gasoline, forming distinct layers in the fuel tank. This phase-separated mixture can damage the engine and fuel system components. Ethanol can also degrade rubber and plastic components in older lawn mowers, leading to leaks and other issues.
The Case for Draining Your Lawn Mower’s Fuel Tank
Given the potential problems associated with leaving gas in a lawn mower, draining the fuel tank before storing it for the off-season is often the recommended approach. This simple step can prevent many of the issues discussed above and extend the life of your mower.
Preventing Gum and Varnish Buildup
Draining the fuel tank eliminates the primary source of gum and varnish formation. By removing the fuel, you prevent the sticky residues from building up in the carburetor and fuel lines. This reduces the likelihood of starting problems and performance issues when you bring your mower out of storage.
Minimizing Corrosion Risk
By removing the gasoline, you also reduce the risk of water absorption and corrosion. An empty fuel tank is less susceptible to moisture accumulation, protecting the metal components of the fuel system. This can significantly extend the lifespan of your lawn mower.
Extending the Life of Fuel System Components
Ethanol-blended fuels can degrade rubber and plastic components. Emptying the fuel tank can mitigate this risk by minimizing the exposure of these components to ethanol over long periods. This is especially important for older lawn mowers with fuel systems that were not designed to withstand the effects of ethanol.
The Alternative: Using Fuel Stabilizers
While draining the fuel tank is a reliable method, there’s another option: using a fuel stabilizer. Fuel stabilizers are additives that help prevent gasoline degradation and protect the fuel system from corrosion.
How Fuel Stabilizers Work
Fuel stabilizers work by inhibiting the oxidation process that leads to gasoline degradation. They contain antioxidants that neutralize free radicals, preventing the formation of gum and varnish. Fuel stabilizers also help protect the fuel system from corrosion and keep the fuel fresh for extended periods.
Some fuel stabilizers also contain water absorbers, which help prevent phase separation in ethanol-blended fuels. By neutralizing the harmful effects of ethanol and preventing degradation, fuel stabilizers can keep your lawn mower running smoothly, even after months of storage.
When to Use Fuel Stabilizers
Fuel stabilizers are particularly useful if you prefer not to drain the fuel tank or if you only store your lawn mower for a relatively short period (e.g., a few months). They are also beneficial for lawn mowers that are used infrequently throughout the year.
How to Use Fuel Stabilizers Effectively
To use a fuel stabilizer effectively, follow these steps:
- Consult the manufacturer’s instructions for the correct dosage. Using too little stabilizer may not provide adequate protection, while using too much can potentially damage the engine.
- Add the stabilizer to the fuel tank according to the instructions.
- Run the lawn mower for a few minutes to ensure that the stabilized fuel circulates throughout the fuel system. This will help protect the carburetor and fuel lines from corrosion and gum formation.
Comparing Draining vs. Using Fuel Stabilizer
Both draining the fuel tank and using a fuel stabilizer are effective methods for preparing your lawn mower for storage. The best choice depends on your individual preferences and circumstances.
Draining the Fuel Tank: Pros and Cons
Pros:
* Most effective method for preventing gasoline degradation and fuel system problems.
* Eliminates the risk of water absorption and corrosion.
* Simple and straightforward procedure.
Cons:
* Requires disposing of the old gasoline properly.
* May require a bit more effort than using a fuel stabilizer.
* Can be messy if not done carefully.
Using Fuel Stabilizer: Pros and Cons
Pros:
* Convenient and easy to use.
* Protects the fuel system from corrosion and gum formation.
* Keeps the fuel fresh for extended periods.
Cons:
* May not be as effective as draining the fuel tank in preventing all fuel-related problems.
* Requires purchasing fuel stabilizer.
* The effectiveness depends on using the correct dosage and following the manufacturer’s instructions.
Step-by-Step Guide: Draining Your Lawn Mower’s Fuel Tank
If you decide to drain your lawn mower’s fuel tank, follow these steps carefully to ensure a safe and effective procedure:
- Safety First: Work in a well-ventilated area and away from any open flames or sources of ignition. Gasoline is highly flammable. Wear gloves and eye protection to prevent skin and eye irritation.
- Gather Your Supplies: You’ll need a fuel-safe container to collect the drained gasoline, a siphon or fuel line clamp, and rags or paper towels to clean up any spills.
- Locate the Fuel Line: Identify the fuel line that connects the fuel tank to the carburetor. It’s usually a rubber or plastic tube.
- Disconnect the Fuel Line: Use a fuel line clamp or pliers to gently disconnect the fuel line from the carburetor. Be prepared for gasoline to flow out.
- Drain the Fuel Tank: Place the fuel-safe container under the fuel line and allow the gasoline to drain completely. You may need to tilt the lawn mower to ensure that all the fuel is removed.
- Dispose of the Old Gasoline Properly: Do not pour old gasoline down the drain or into the ground. Take it to a local recycling center or hazardous waste disposal facility.
- Reconnect the Fuel Line: Once the fuel tank is empty, reconnect the fuel line to the carburetor. Ensure that the connection is secure.
- Run the Engine (Optional): If you want to completely empty the carburetor, you can try starting the lawn mower and letting it run until it stalls due to lack of fuel. This will ensure that no fuel remains in the carburetor. However, this is not always necessary.
A Word on Fuel Type: Ethanol-Free Gasoline
If you have access to ethanol-free gasoline, consider using it in your lawn mower. Ethanol-free gasoline is less likely to cause problems related to water absorption and corrosion. Ethanol-free gasoline is generally more stable than ethanol-blended fuels and can be stored for longer periods without degrading.
While it may be slightly more expensive, the benefits of ethanol-free gasoline can outweigh the cost, especially for older lawn mowers that are not designed to handle ethanol.
Maintaining Your Lawn Mower for Longevity
Regardless of whether you choose to drain the fuel tank or use a fuel stabilizer, regular maintenance is essential for ensuring the longevity of your lawn mower.
- Change the Oil Regularly: Follow the manufacturer’s recommendations for oil changes. Dirty oil can damage the engine and reduce its lifespan.
- Clean or Replace the Air Filter: A dirty air filter restricts airflow and can lead to poor engine performance.
- Sharpen or Replace the Blades: Dull blades tear the grass instead of cutting it cleanly, making your lawn more susceptible to disease.
- Clean the Mower Deck: Remove grass clippings and debris from the mower deck after each use to prevent rust and corrosion.
- Store Your Lawn Mower Properly: Store your lawn mower in a dry, protected area to prevent rust and damage.
Conclusion: Make an Informed Decision
Whether you decide to leave gas in your lawn mower with a fuel stabilizer or drain it completely, the key is to be informed and proactive. Understanding the potential risks and benefits of each approach allows you to make the best choice for your specific situation. By following the guidelines outlined in this article and implementing a regular maintenance schedule, you can keep your lawn mower running smoothly for many years to come, saving you time, money, and frustration. Remember that consistent care is always more effective than reactive repairs.
Is it really that bad to leave gas in my lawn mower over the winter?
Leaving gasoline in your lawn mower over the winter months can indeed cause problems. Gasoline, particularly modern blends with ethanol, can degrade over time. As it degrades, it can form gum and varnish deposits that can clog the carburetor and fuel lines. These deposits can make it difficult, if not impossible, to start your lawn mower in the spring, leading to costly repairs.
Furthermore, the ethanol in gasoline attracts moisture. This moisture can lead to corrosion within the fuel system, especially in older mowers. Water accumulation can also separate from the gasoline and settle at the bottom of the fuel tank, further hindering the mower’s ability to start and run smoothly. For these reasons, draining or treating the gas is generally recommended for winter storage.
What’s the best way to stabilize the gasoline in my lawn mower if I can’t drain it completely?
The best way to stabilize gasoline is by using a fuel stabilizer specifically designed for small engines. These stabilizers contain additives that prevent the gasoline from degrading, minimize moisture absorption, and protect against gum and varnish formation. Simply add the correct amount of stabilizer to the fuel tank according to the product instructions, and then run the engine for a few minutes to ensure the treated fuel circulates throughout the fuel system.
Make sure to follow the instructions on the fuel stabilizer bottle carefully. It’s crucial to use the correct amount for the volume of gasoline in the tank. Running the engine after adding the stabilizer helps to coat all the internal parts of the fuel system, providing comprehensive protection against degradation and corrosion during storage. This ensures a smoother start and reliable performance when you need to use your lawn mower again.
If I drain the gasoline, should I also drain the carburetor?
Yes, draining the carburetor is highly recommended if you’re draining the gasoline tank. The carburetor holds a small amount of fuel even after the tank is empty. This remaining fuel is just as susceptible to degradation and gum formation as the fuel in the tank. Leaving it in the carburetor can lead to clogging and starting problems in the spring.
To drain the carburetor, locate the drain screw or bowl on the bottom of the carburetor. Place a container underneath to catch the fuel, and then loosen the drain screw. Allow all the fuel to drain out completely. Once drained, retighten the drain screw to prevent leaks. This simple step can significantly improve the reliability of your lawn mower’s starting performance after winter storage.
Are there any alternatives to gasoline that I can use in my lawn mower?
While most lawn mowers are designed to run on gasoline, there are alternative fuel options emerging, particularly with advancements in electric and battery-powered mowers. These alternatives eliminate the issues associated with gasoline degradation and the need for fuel stabilization. Electric mowers, powered by rechargeable batteries, offer a cleaner and more convenient solution for many homeowners.
Consider the size of your lawn and your cutting needs when evaluating alternatives. Battery-powered mowers are generally suitable for smaller to medium-sized yards, offering quieter operation and reduced maintenance compared to gasoline-powered mowers. However, they may not be as powerful as gasoline engines for tackling very thick or overgrown grass. As technology advances, expect to see more innovative and efficient fuel alternatives for lawn mowers in the future.
Is it okay to use old gasoline from a container that’s been sitting for a while in my lawn mower?
It is generally not recommended to use gasoline that has been sitting in a container for an extended period, especially if it’s more than a few months old. Gasoline degrades over time, and old gas can lead to starting problems, poor engine performance, and potentially damage to the fuel system. The lighter components of the gasoline evaporate, leaving behind a thicker, less volatile residue that can clog jets and filters.
If you’re unsure about the age or condition of the gasoline, it’s best to dispose of it properly and purchase fresh fuel. Using fresh gasoline ensures optimal combustion and prevents potential problems caused by degraded fuel. Always store gasoline in a tightly sealed container in a cool, dry place to minimize degradation. Properly disposing of old gasoline is also crucial for environmental safety.
What if I forget to drain or stabilize the gas and my lawn mower won’t start in the spring?
If you forget to drain or stabilize the gas and your lawn mower won’t start in the spring, the first step is to try draining the old gasoline and replacing it with fresh fuel. Sometimes, this simple step is enough to resolve the issue. However, if the mower still doesn’t start, the carburetor is likely clogged with gum and varnish deposits.
In this case, you may need to clean or rebuild the carburetor. This can involve disassembling the carburetor, cleaning the jets and passages with carburetor cleaner, and replacing any worn or damaged parts. If you’re not comfortable performing this task yourself, it’s best to take the lawn mower to a qualified repair technician. Professional cleaning or rebuilding of the carburetor will likely restore the mower’s starting performance.
Does the type of gasoline I use affect how well it stores in my lawn mower?
Yes, the type of gasoline you use can significantly impact how well it stores in your lawn mower. Gasoline containing ethanol, especially E10 (10% ethanol), is more prone to absorbing moisture from the air, leading to phase separation and corrosion. This can cause more rapid degradation of the fuel and potential damage to the fuel system.
Consider using ethanol-free gasoline, if available, particularly for long-term storage. Alternatively, use a fuel stabilizer specifically designed to combat the effects of ethanol. These stabilizers help to prevent moisture absorption and keep the fuel stable for extended periods. Always check your lawn mower’s owner’s manual for recommended fuel types and storage guidelines.