How to Start Lawn Mower with Old Gas

Starting a lawn mower with old gas can be a challenging task, especially if the fuel has been sitting in the tank for an extended period. Over time, gasoline can break down and develop gum and varnish that may clog the fuel system, leading to engine issues.

However, with the right steps and a bit of patience, you can safely start your mower and ensure it operates smoothly, even with older fuel. In this guide, we’ll walk you through how to start lawn mower with old gas, to effectively start your lawn mower while dealing with old gas.

Importance of Proper Fuel Management

Proper fuel management is crucial for the longevity and performance of your lawn mower. Using fresh gasoline not only helps in starting the engine more efficiently but also minimizes the risk of fuel system damage caused by gumming and varnishing. Old gas can lead to inconsistent engine performance, increased emissions, and potential mechanical failures.

By routinely checking and replacing your fuel, as well as storing it correctly in a cool, dry place, you can ensure that your mower operates at its best. Additionally, implementing a fuel tracking system to monitor fuel age can further prevent complications associated with stale gasoline, allowing for smoother mowing sessions and a longer lifespan for your equipment.

Understanding the Risks of Using Old Gas

Using old gas in your lawn mower can pose several risks that may compromise its performance and longevity. When gasoline sits for an extended period, it undergoes chemical changes that can lead to a decline in quality.

The breakdown of hydrocarbons can result in the formation of gum and varnish, which can clog fuel lines, filters, and the carburetor. This not only makes starting the mower more difficult but can also lead to engine misfires and reduced power output. Furthermore, old gas may not ignite as efficiently, causing increased emissions and potentially damaging the engine due to irregular combustion.

To avoid these issues, it’s important to regularly check the age of the fuel in your mower and dispose of any gasoline that has been sitting for too long.

10 Methods How to Start Lawn Mower with Old Gas

1. Check the Gasoline for Degradation

Before attempting to start your lawn mower with old gas, it’s crucial to check the condition of the gasoline. Gasoline that has been sitting for a long time can become stale or contaminated, which can affect engine performance.

Pour a small amount of the old gas into a clear container and inspect it for any changes in color, smell, or consistency. If the gas appears dark, has a sour odor, or contains sediment or sludge, it may be too degraded to use effectively. If the gas seems relatively unchanged, it may still be usable, but proceed with caution.

2. Drain the Old Gasoline

To prevent any potential issues with the engine, consider draining the old gasoline from the lawn mower’s fuel tank before attempting to start it. This can be done by using a siphon pump or by carefully removing the fuel tank and pouring out the old gas.

Draining the old gas helps eliminate the risk of introducing degraded fuel into the engine, which can cause starting problems or damage. After draining the old gas, refill the tank with fresh gasoline to ensure optimal engine performance.

3. Add a Fuel Stabilizer or Conditioner

If draining the old gas is not feasible, you can add a fuel stabilizer or conditioner to the existing fuel in the tank. Fuel stabilizers are designed to restore some of the lost qualities of stale gasoline and improve its combustibility.

Pour the recommended amount of stabilizer or conditioner into the fuel tank and gently shake or swirl the tank to mix it with the old gas. Allow the mixture to sit for a few hours to give the stabilizer time to work. This method can help improve the chances of starting the mower with old gas.

4. Clean the Fuel System Components

Old gasoline can cause clogs and deposits in the fuel system components, such as the carburetor, fuel filter, and fuel lines. Before attempting to start the mower, inspect and clean these components to ensure they are free from any obstructions.

Use a carburetor cleaner to clean the carburetor, and replace the fuel filter if it appears dirty or clogged. Clearing out the fuel lines with compressed air or a fuel system cleaner can also help remove any residue that may affect the engine’s ability to start.

5. Prime the Engine

Many lawn mowers have a primer bulb that helps deliver fuel to the engine when starting. If you are using old gas, it’s important to prime the engine properly to increase the likelihood of a successful start.

Press the primer bulb several times (usually about 5 to 10) to draw fuel from the tank into the carburetor. This action helps ensure that the engine receives the necessary fuel mixture to start, even if the gas has been sitting for a while. Make sure to follow the manufacturer’s instructions for priming the engine.

6. Check the Spark Plug

A worn or fouled spark plug can make it difficult to start the lawn mower, especially when using old gas. Before attempting to start the mower, remove the spark plug and inspect it for signs of wear or carbon buildup. If the spark plug is dirty or worn out, clean it with a wire brush or replace it with a new one. A properly functioning spark plug is essential for igniting the fuel-air mixture in the engine and ensuring a smooth start.

7. Use Starting Fluid

If the lawn mower still refuses to start with old gas, you can use a starting fluid as an additional aid. Starting fluid is designed to help engines start more easily by providing a highly flammable mixture that ignites quickly.

Spray a small amount of starting fluid directly into the carburetor or air intake while pulling the starter cord. This can help kick-start the engine and overcome the difficulties associated with using old gas. Be cautious not to overuse starting fluid, as it can damage the engine if applied in excess.

8. Perform a Thorough Inspection

Before starting the mower, perform a thorough inspection to ensure that all components are in good working condition. Check the oil level and quality, as old gas can affect the engine oil and may require a change.

Inspect the air filter for dirt or debris, and clean or replace it if necessary. Ensure that all connections, including fuel lines and electrical wires, are secure and free from damage. A comprehensive inspection helps identify and address any potential issues that could affect the mower’s performance.

9. Crank the Engine in Short Bursts

When attempting to start the lawn mower with old gas, try cranking the engine in short bursts rather than continuously pulling the starter cord. Pull the starter cord a few times and then pause to allow the engine to rest.

This method helps prevent flooding the engine with excess fuel and allows the old gas to be used more efficiently. If the engine shows signs of starting but then stalls, allow it to rest briefly before trying again. This approach can increase the chances of a successful start without overloading the engine.

10. Be Patient and Persistent

Starting a lawn mower with old gas can be a test of patience and persistence. If the mower does not start immediately, avoid the temptation to continuously crank the engine, as this can lead to further complications.

Instead, take a break and let the engine rest before trying again. Sometimes, it may take several attempts to get the mower started with old gas. Remain persistent and methodical, making adjustments as needed, and eventually, the mower should start and run smoothly.

Tips for Achieving the Best Performance with Your Lawn Mower

1. Regular Maintenance: Schedule regular checks and maintenance for your lawn mower, including oil changes, air filter replacements, and spark plug inspections. Keeping the mower well-maintained ensures optimal performance and longevity.
2. Use Fresh Fuel: Always use fresh gasoline and consider adding a fuel stabilizer to prevent fuel degradation if the mower will not be used for an extended period. This helps maintain engine performance and reduces starting issues.
3. Clean the Mower After Use: After mowing, clean the deck and remove any grass clippings and debris. This prevents corrosion and build-up, which can affect the mower’s performance.
4. Proper Storage: Store the lawn mower in a dry, sheltered location to protect it from the elements. Consider using a cover to shield it from dust and moisture, which can lead to rust and other issues.
5. Adjust Cutting Height: Adjust the mowing height based on the season and grass type. Mowing at the appropriate height encourages healthy growth and a more attractive lawn.
6. Check Tire Pressure: Ensure that the tires are adequately inflated for better traction and performance. Low tire pressure can affect cutting efficiency and lead to uneven mowing.
7. Practice Safe Operation: Always follow safety guidelines when operating your lawn mower, including wearing proper footwear and eye protection. Additionally, avoid mowing in wet conditions to reduce the risk of slipping and ensure a clean cut.
8. Keep Blades Sharp: Regularly inspect and sharpen the mower blades. Sharp blades create a clean cut, promoting healthy grass growth and preventing damage to the plant.

Common Mistakes to Avoid

1. Neglecting Regular Maintenance: Skipping routine checks and servicing can lead to decreased performance and more significant issues down the line. Always adhere to a maintenance schedule for oil changes, filter replacements, and spark plug inspections.
2. Using Old Fuel: Improper storage of fuel or using gasoline that has gone stale can result in starting difficulties and poor engine performance. Always use fresh fuel and consider adding fuel stabilizers if the mower will sit unused for an extended period.
3. Ignoring Blade Maintenance: Failing to consistently sharpen the mower blades can lead to ragged cuts, which can stress grass and invite disease. Make it a habit to check and sharpen the blades regularly for the best results.
4. Improper Cutting Height: Mowing at an incorrect height can damage the grass and inhibit healthy growth. Adjust your cutting height according to seasonal needs and the specific grass type to promote a thriving lawn.
5. Overlooking Tire Pressure: Running the mower with improperly inflated tires can compromise traction and lead to uneven mowing. Regularly check and maintain proper tire pressure to enhance performance.
6. Mowing in Wet Conditions: Operating the mower on wet grass can result in clumping, and uneven cuts, and increase the risk of slipping. Avoid mowing when conditions are damp to ensure a clean cut and maintain safety.

Conclusion

Starting a lawn mower with old gas requires careful preparation and attention to detail to ensure a successful outcome. By checking the condition of the gasoline, draining it if necessary, adding a stabilizer, cleaning the fuel system, priming the engine, and inspecting key components, you can improve your chances of getting the mower running. Thanks for reading, and we hope this has given you some inspiration on how to start lawn mower with old gas!