How To Drain Gas From Lawn Mower in 4 Easy Steps

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As one of the most valuable machines for yard maintenance, having a perfectly working lawn mower is a must.

It ensures your lawn is healthy, giving your property a clean and neat look, as well as a welcoming vibe.

That said, you will have to learn about proper lawn mower maintenance to keep it in running condition for longer.

Among many things, these include knowing why, when, and how to drain gas from lawn mower.

Why and When To Do It

If you own a gas-powered lawn mower, it’s important to learn about removing gas from the tank to extend its lifespan.

Why? That’s because your machine will most likely stay in storage for months during the winter.

In fact, even if it’s not winter, we recommend emptying the fuel tank if you don’t plan on using your lawn mower for three months.

If you use E10 gasoline on your lawn mower, you’d be doing your machine a favor if you drain the tank every three weeks.

Failure to do this means the fuel stays in the tank for a long time, resulting in it going bad and losing combustibility.

Old gasoline becomes almost varnish-like and may cause congestion in the lines and carburetor.

When this happens, you will notice your lawn mower having performance problems, like:

• Sputtering or harder to start the engines
• Unusual noises while usage
• Not starting
• Killing the mower for good

How To Tell If Gas Is Bad

Before draining the tank for maintenance, it’s important to learn if the gas is still usable or not.

This way, you can decide if you can use it for other stuff or dispose of it entirely.

Here’s how you can tell if the fuel in your lawn mower’s tank is still good:

By Appearance

You can easily observe if your gas has gone bad through the change in its color. To do this, follow these easy steps:

Step 1: Prepare two transparent cups.

Step 2: In the first cup, pour a fresh gas for comparison.

Step 3: From your gas tank, scoop a portion of gas and transfer it to the second cup.

You’ll know when the gas from your tank is bad when it’s significantly darker than the cup with the fresh gas.

By Smell

Take your mower someplace where you can focus on the smell of the fuel in the tank.

Note that you will only be needing a whiff, so don’t put your nose too close to the gas tank.

As you open the lid, you should be able to distinguish the smell right away.

If it is stronger than the smell of freshly bought gas, this confirms it has gone bad.

You will know it’s bad when the gas has a sour and decaying smell to it.

How To Drain Gas From Lawn Mower

Before you learn how to drain gas from lawn mower, you will need to prepare a few things first.

More often than not, you already have these in your garage:

• Siphon pump and hose
• Gas can or a container with lid for proper dumping
• Safety gloves and goggles
• Tarp or any extra flooring layer
• Rags for cleaning

After gathering all the needed supplies, follow these steps:

Step 1: Ready your mower.

Start by parking your lawn mower on an even surface, handbraked and keys off.

Tipped or incorrectly tilted mowers might cause fuel to travel to other parts of the machine.

When that happens, it could result in damage to your carburetor and engine.

Step 2: Gear up and prep the workspace.

Since you’ll be dealing with combustible materials, make sure there are no open flames near your workspace.

Also, it’s important that you gear up by wearing safety gloves and goggles.

It is advisable to lay out an extra layer of flooring, such as a tarp, to avoid fuel stains on the ground.

By following this trick, you won’t have to worry about scraping oil from the ground afterward.

Lastly, pull out the spark plug to ensure the engine doesn’t turn on accidentally.

Step 3: Drain with siphon pump and hose.

You can empty the tank using any tube or hose, but we don’t recommend it.

You could end up ingesting fuel, even just a little bit, if you use your mouth to get the gas out the other end of the tube.

To be safe, use a siphon pump and hose instead.

Grab a gas can and place it not too far from your lawn mower’s tank, keeping in mind the length of the hose.

Insert one end of the hose into the fuel tank and the other end into the can.

Then, as you squeeze the pump, you will see the gas coming out and into the container.

Without a pump

If you don’t have a siphon pump, that’s also not a problem. You can use a single siphon hose as an alternative instead.

While it may require more effort, you can expect to see the same results.

To do this, start by inserting the brass-end side of the hose into the tank. Then, put the other end into your gas can or container.

You will need to pull and push the tube several times for it to start siphoning gas out of the tank.

Step 4: Drain fully and dispose of the fuel.

Whether you use a siphon pump or not, there’s a good chance you will still end up with leftover gas in the tank.

Especially if it’s old gas, you will want to remove every last drop.

One trick is to pour a small amount of fresh gas into the tank to soften the stale gas.

Then, siphon it out again to remove all the remaining gas. Some use a rag to remove dirt buildup at the same time.

What do you do with the can full of unusable gas?

Consult local authorities about your area’s guidelines on disposing of combustible materials.

Draining Gas From Lawn Mower

In the past, it was common practice to let the lawn mower run until it ran out of gas.

As you can imagine, doing so releases toxic emissions that we now know are harmful to humans, pets, and the environment.

By following the tips we shared here, we’re sure you won’t have a hard time draining your lawn mower’s fuel tank before the winter comes.