How to dispose of gas in a lawnmower, step by step


You have been trying hard all day by pulling the lawnmower’s pull cord repeatedly, but it won’t start? You have tried some fixes like changing the lawnmower’s oil, replacing the air filter, and even the sparkplug. But everything looks fine, but still, your lawnmower won’t give a buzz. If your machine hasn’t been put into use for a long time, then the chances are that the lawnmower has got bad gas. In this case, you need to dispose of the bad gas and refill it with fresh gas. Removing the gas from the tank is also necessary for some other fixes. This blog post will help you with a step-by-step method of removing the gas in your lawnmower.

How to dispose of gas in a lawnmower, step by step:

  • Step 1. Locate the gas tank.
  • Step 2. Verify if you have bad gas.
  • Step 3. Clean the area around the gas tank.
  • Step 4: Dispose of the gas from the tank.
  • Step 5: Dispose of the gas from the carburetor.
  • Step 6: Install the fuel line back.
How to dispose of gas in a lawnmower, step by step 1

Why do I need to remove gas from my lawnmower tank?

Gas is the fuel for a lot of lawnmowers. There can be several reasons why you need to empty your gas tank. One of the more frequent causes is bad gas. Keeping old gas in the tank for a long time can make the gas go bad. The old gas has hydrocarbons that react with oxygen to produce new compounds, resulting in oxidization. This creates a gum-like substance that can clog gas lines, fuel filter, and carburetor. Other reasons for removing the gas from the tank are fixes where the fuel line needs to be disconnected or if you need to tip your mower to reach the bottom of your lawnmower.

Safety Measures:

Before starting to work with removing the gas it is really important to have a look at some important safety measures. Gas is toxic and can cause severe issues if it enters your eyes or if it catches a flame. So, the following safety measures must be taken before moving forward:

Wear Safety glasses: You must wear safety glasses to prevent the gas from entering your eyes as it can cause severe damage to them.

Wear safety gloves: During the gas disposal from the gas tank, it is assured that the gas shall come on to your hands. So, you must wear safety gloves to protect yourself from unnecessary injuries.

No open flames: Gasoline is a highly inflammable material and immediately catches fire if exposed to even a tiny flame. So, there should not be any open flames around your area of operation

Step 1. Locate the gas tank:

  • All the lawnmowers have a gas tank where you fill in the gas regularly.
  • Usually, the gas tank is easy to locate, just beside the carburetor. You can see a fuel line going from the gas tank into the lawnmower’s carburetor.

Step 2. Verify if you have got bad gas:

If the reason for removing gas from your gas tank is bad gas, you should do some quick checks to verify if it is really bad. If you have another reason for removing gas from your tank, you can skip this step.

Causes of low-quality gas:

Dirty gas:

Bad gas may be caused because of some dirt or debris that might have gone inside the gas tank while it’s filling. Or rust if you have an older metal gas tank.

Old gas:

It may also be caused if the lawnmower hasn’t been put to use for a long time. The gas that has been in the lawnmower for more than two months may thicken and produce a thin covering on the tank’s inside wall and the fuel line, which halts the lawnmower from starting.

Checking the lawnmower for bad gas:

Step 2.1. Open the gas tank’s cap:

Open the gas tank’s cap.

Step 2.2. Smell the gas:

Give a little sniff to the gas escaping from the tank. Keep some distance from the tank while doing so because these gases are toxic and affect your health.  If the gas smells like more kerosene than gas, it indicates that the gas has gone bad and needs to be disposed of.

Step 2.3. Close the gas tank’s cap:

Close the gas tank’s cap to prevent further gas from escaping the tank.

Step 3: Clean the area around the gas tank:

It is recommended to clean the area around the gas tank because dirt and debris can again enter the gas tank or the carburetor once you start the disposal of old gas. There are many ways to do this. You can use water, a clean towel, or spray spirit using a paintbrush. We shall discuss how to clean the area around the gas tank using a garden hose step by step.

Step 3.1. Spray water on the area around the gas tank:

Set your garden hose at low pressure and spray some water on the area surrounding the gas tank. This area includes the fuel line and the carburetor.

Step 3.2. Rinse off the area:

Now, using a clean, dry cloth, wipe the entire area. You can also use compressed air for this purpose.

Step 4: Dispose of the gas from the gas tank:

With the cleaning done, it’s time to dispose of the old gas out from the gas tank using the following steps:

Step 4.1. Place an oil catch can:

Place an oil catch can below the lawnmower. It shall be used to catch and hold the gas while it is being disposed off.

Step 4.2. Loosen the fuel line bracket:  

Using a pair of pliers, hold the two notches attached to the bracket and push them together. Wiggle the pliers so that the bracket gets loosened and slips away from the carburetor. 

Step 4.3. Remove the carburetor’s fuel line:

Once the bracket has been loosened, use your hands and push back that end of the fuel line attached to the carburetor.

Step 4.4. Let the gas drain entirely through the hole:  

All the lawnmowers have a tiny hole just below the fuel line used to drain the gas from the lawnmower. Now, let the gas drain through this hole. The gas goes right into the oil catch that has been placed below the lawnmower. Wait for a few minutes until the gasoline has been disposed off entirely and the gas tank gets empty.

Step 5: Dispose of the gas from the carburetor:    

If you have disposed of all the gas from the gas tank, that’s not all. There might be some of the old gas still left in the carburetor. So, it would be best if you disposed of that as well.

Step 5.1. Take off the screw at the bottom of the carburetor:

There is a screw at the bottom of the carburetor that serves as a jet as well. Using a screwdriver, loosen this screw and remove it from the carburetor. Let the gas drain out completely.

Step 5.2. Clean the jet:

  • The carburetor jet gets gas from the gas tank and supplies it to the desired point using three tiny holes.
  •  There might be a tiny spec of dirt stuck inside any of these holes, which may result in halting the lawnmower’s starting procedure.
  • So, blow some compressed air into these holes.
  • If you don’t have compressed air available, you can blow some air using your mouth, but it is not recommended.

Step 5.3: Install the carburetor screw back:

Install the carburetor screw back using a screwdriver.

Step 6: Install the fuel line back:

Step 6.1: Attach the fuel line back:

Attach the fuel line end detached from the carburetor back using your hand.

Step 6.2: Tighten the bracket:

Using a pair of pliers, hold the two notches on the bracket (that was slid away from the carburetor) and push these notches together. Slide the bracket back until it reaches the junction of the fuel line and carburetor.

The gas has now been successfully disposed of from the lawnmower’s gas tank, and you may now refill the gas tank with new, fresh gas to relieve your lawnmower.

Related Questions:

1. What is the best lawnmower gas?

The best gas for a lawnmower is the one that has the following features:

  • It should be clean and fresh
  • Should have a minimum of 87 octane, in case you are operating at high altitudes
  • Should have 10% ethanol or up to 15% MTBE
  • You can also use a canned fuel product such as Briggs & Stratton Advanced Formula Ethanol-Free Fuel.

2. Should I use a fuel stabilizer?

  • A fuel stabilizer is a solution that protects the gas in the lawnmower. It is usually made from petroleum products and combines with gasoline to prevent evaporation. Doing so prevents the gasoline from forming sticky particles that get stuck in the carburetor and can ruin it.
  • Fuel stabilizers aren’t recommended for daily use vehicles; however, for seasonal equipment such as lawnmower, it is highly recommended to use a fuel stabilizer to avoid gasoline evaporation.

Final Remarks:

If gardening improves your mood, then the lawnmower must be maintained and well cared for. It isn’t enjoyable when you try to start your lawnmower, but it won’t start. One of the more frequent reasons is old gas. The lawnmower’s old gas can easily be removed at home with the help of this blog. Besides old gas, there can be several other reasons you want to remove gas from the tank. Don’t forget to take precautionary measures while performing the disposal process.

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