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Easy Tips to Start a Lawn Mower with Old Gas

Easy Tips to Start a Lawn Mower with Old Gas

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The lawn mower is one of the most essential pieces of equipment that you will want to keep in your shed, especially if you like to carry out landscaping work on the lawn from time to time.

Most people keep their lawn mowers in the shed during the winter season, and start taking them out after the spring season ends. However, taking your lawn mower out after a period of hibernation is not as easy as you might think.

Usually, getting the lawn mower going after a period of hibernation is a bit difficult, but you can usually get the lawn mower working after a bit of pulling with the pull rope and a considerable amount of swearing.

But, if you can’t get the lawn mower going properly, the reason is probably due to the humidity in the environment. Sometimes, it’s difficult to get the lawn mower started because of the humidity.

In areas with higher humidity, water begins to condense inside the fuel tank and the carburetor, and this eventually mixes in with the gas. This also affects the spark formation of the plug.

To get the mower started, the best solution is to replace the gas and clean the plugs. In some situations, your only option might be to replace the plugs altogether.

Now, you need to understand that there are quite a few reasons why gasoline tends to go bad in old lawn mowers. But first, let’s focus on what causes the gasoline to break down in the first place.

The first thing you need to understand is the gas’s volatility.

The lightest chemicals tend to evaporate much quicker than others, which ultimately leaves a much heavier gasoline that fails to combust in a proper manner.

There’s a strong chance that the engine will run, but it’s not going to run as well.

Another major reason why the gas goes bad is because of oxidation.

Oxidation is caused by hydrocarbons found in the fuel, which reacts with the oxygen to create new compounds. This creates a type of gum that causes clogging in the filters and gas lines.

This ultimately causes deposits in the fuel system. Once the carburetor gets gummed up, it can cost you a small fortune to fix, and there’s a strong chance that the carburetor might not run at all until the deposits are thoroughly removed.

When water finds its way into the fuel tank via condensation (usually due to the fluctuating temperatures), it can lead to a series of other problems.

But, what can you do about it? If you have just remembered that there’s old gas in the lawn mower, there’s no need to worry.

Easy Tips To Start A Lawn Mower With Old Gas

Here are just a few tips for starting a lawn mower that has old gas inside of it and getting it purring in no time.

Clean Out the Tank

The gas tank of your lawn mower needs to be cleaned out properly.

Now, in general, it is highly recommended that you clean out the gas tank of your lawn mower before you let it sit for a longer period of time. But, most people don’t really know about this, nor do they care.

So, the first thing that you need to do is clean out the gas tank.

Make sure you get rid of all the old gas thoroughly, clean the spark plugs, and then make sure that everything is in pristine condition from the inside before you decide to fill up the tank with more gas.

You need to make sure that you get rid of all the build up from your tank, and then fill it up. If there is residue inside the tank, you should consider getting rid of it as thoroughly as you can.

When removing the gas, make sure you siphon it properly and then place it in a container. You need to properly dispose of the gas, and it’s best if you do it in the right manner.

You need to run a siphon hose from the gas tank to another container in which you are going to keep the gas. Then, you just have to pump it a few times and let the gas travel from the tank to the container.

Remember, do not use water to clean the gas tank. Once the gas has been siphoned off properly, just check inside for any residue before filling new gas in the container.

Check the Spark Plugs

Once you have cleaned the tank and added new gas in the container, the next step is to check for the spark plugs.

When you add new gas to the fuel tank, it’s going to help prime the fuel tank and it’s going to make the lawn mower run significantly better, almost as if it was new.

But, if the lawn mower still doesn’t start, you might be looking at an issue with the spark plugs.

When the lawn mower has been kept in storage for a long period of time, there is a considerable possibility that the spark plug wiring might have become loose.

You might want to check the wiring to the spark plug, and more importantly, make sure that the plug itself is clean.

You need to push the spark plug all the way in to ensure that there’s a firm connection.

Once you are done, you should try to restart the lawn mower.

Again, it’s also important to note that the spark plug needs to be replaced after every year or so.

The spark plugs are relatively inexpensive, so you don’t have to spend a lot of money either. Replacing the spark plugs will simply improve engine performance and keep it running smoothly for a longer period of time.

Avoid Flooding the Carburetor

If you want to start the engine after a long time, you might want to avoid flooding the carburetor.

This is a very common mistake that people make when it comes to starting their lawn mower after a long while.

When you try to power it on, you have to be mindful of the sounds and the smells that are being created by the lawn mower.

If the smell of the gas becomes incredibly strong, you should immediately stop trying to restart the lawn mower.

A strong smell of gas usually indicates a serious problem: flooding in the carburetor. Just give it a little while before you try to restart the lawn mower again.

Use Ethanol-Free Gasoline

If you are particular about what you use when you are trying to restart the lawn mower, you might want to consider using some good old fashioned gasoline that is ethanol free.

These types of gases are a bit more expensive, but they give you the added advantage that you don’t have to worry about cleaning the gas tank before you keep it in the shed.

The best thing about this type of gas is that it requires very little in the way of maintenance, and it’s also going to fire up right away when you turn it on after a long while.

Obviously, these are not issues that you want to repeat every year. Bad gas is going to leave a terrible impact on your engine, and there is a pretty strong chance that the engine performance will be affected.

The useful life span of your lawn mower is also going to be affected as a result.

Thankfully, there are quite a few maintenance tips that you can follow to keep your lawn mower in prime condition.

Lawn Mower Maintenance

Lawn Mower Blade

Here are some basic things to help you with lawn mower maintenance and to ensure that your lawn mower lasts you a long time without requiring any major repairs.

Sharpen the Blades

To ensure that your lawn mower continues to function properly for a longer period of time and maintains its effectiveness, you need to sharpen the blades on a regular basis.

Ideally, you should sharpen the blades at least once or twice per year. This will keep the blades in prime condition and also ensure that your lawn mower continues to run smoothly.

Check the Oil

More importantly, you need to check the oil in the engine.

Before you turn on your lawn mower for the first time in the season, you need to check the oil levels in the engine.

Making use of a dipstick is a great way to check the level of oil and top it off as necessary.

Check the Air Filter

When was the last time you replaced the air filter of your lawn mower?

The air filter should be absolutely clean and must also be free of debris.

If the air filter isn’t too clogged, you might want to clean it properly. But, if the air filter is considerably dirty, you should consider replacing it outright.

Air filters are as inexpensive as can be, and replacing it at least once a year is definitely not a bad idea.

It’s going to keep the engine running smoothly and it will also ensure that the performance of the engine isn’t affected.

Take a Look at the Tires

The tires of your lawn mower are subject to a considerable amount of degradation, so it’s recommended that you take a look at the tires.

First of all, make sure that the tires are fully inflated. If there’s a puncture, you need to get it fixed.

This is going to improve the performance of your machine and ensure that it runs smoother for a longer period of time.

Basic Cleaning

After every time you use the lawn mower, you need to carry out basic cleaning work.

Obviously, you need to check whether the lawn mower is free of debris and is completely clean before it goes into the shed again.

There’s really not a lot involved in this; you just need to make sure that you check whether there are any clumps of grass or other debris that is stuck underneath.

As long as you don’t have a riding mower, all you have to do is turn the lawn mower on the side and then check that there’s nothing stuck underneath.

Replacing the Oil

Depending on the frequency of usage, you might want to keep an eye out on the level of oil.

We have already talked about how important it is to check the oil levels in a gas-powered lawn mower. If the level of oil is low, it could cause serious damage to the engine.

Most people tend to forget when they have to add oil to the engine, so the best thing that you can do is make a practice of checking the oil every time you add more fuel.

This is a simple habit that will help you protect the engine and keep it running in prime condition.

After the Mowing Season Ends

As the summer draws to a close and you start wrapping up the lawn mower, there are a few things that you need to do.

First and foremost, you need to remove the fuel. If you leave fuel in the lawn mower, it could eventually go bad, and you will have to repeat the steps given above all over again.

Another thing that could be a serious issue is that the bad gas can cause corrosion inside the innards of the lawn mower.

Just take it out, and then add fuel the next time you are going to use the lawn mower.

Remove the Battery

If you have a conventional battery powered motor, you should avoid leaving the battery inside throughout the course of the winter.

You need to remove the battery, and then charge it after a few times to keep it in the best possible condition.

If the battery is left without any charge for more than six months, it’s probably going to die the very next year.

These are just a few things that you should know about maintaining your lawn mower and making sure that it continues to run smoothly.

You need to perform adequate lawn mower maintenance to ensure that the machinery continues to run smoothly. Remember, it’s all about keeping a firm eye on the lawn mower and carrying out repairs and maintenance as needed.


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