How to Drain Gas from your Generator Safely?

How to Drain Gas from your Generator Safely?

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Draining gas from your portable generator’s fuel tank is one of the most reliable ways to store a generator and ensure its longevity. 

Siphoning the gasoline from your generator before storing prevents fuel-related issues. It helps boost your generator’s life, prevents costly maintenance, and most importantly keeps it ready for the upcoming season.

But, how to drain gas from your generator safely?

In this post, we’ll take a look at the various ways to drain your generator’s fuel tank safely. We’ll also talk about the safety aspects you need to keep in mind before draining your fuel tank. Lastly, we’ll talk about how to store and discard the drained fuel.

But, let’s start by answering why is it good to drain the fuel tank of your generator before long-term storage.

Do I Need to Drain Gas from my Generator?

No, you don’t have to drain gas from your generator if you’re going to add a fuel stabilizer before winterizing. However, draining gas from the generator is the most reliable way to prevent fuel-related issues in long-term generator storage.

When generators with fuel in the tank stay in storage between camping seasons, the gasoline starts degrading. Gasoline, especially ethanol-blended, readily absorbs water from moisture which results in oxidization of the gas.

As time goes, the oxidation increase until the gas in the fuel tank becomes stale. Stale fuel when unchecked gums and clogs up the whole fuel system preventing your generator from starting when you need it.

Though, you can use a fuel stabilizer like STA-BIL or SeaFoam to prevent oxidation if draining the fuel tank is not something you want to tackle. However, for the rest of us, draining gas from generators is the safest approach for long-term storage.

Do all Generator’s Gas need to be Drained?

Generators that run on liquid fuel like gasoline and diesel need to be drained or stabilized before storage. However, portable generators that run on propane don’t need to go through the process of draining or stabilizing before winterizing.

Because both gasoline and diesel oxidize when they come in contact with oxygen, you need to take proper measures when storing them. Therefore, generators running on gas or diesel will have to be either stabilized or drained.

On the other hand, propane is a gas and can be stored indefinitely without any issue. Thus, dual-fuel generators using propane don’t have to worry about propane going stale.

Read More: Find reviews of both dual-fuel and inverter portable generators for your RV.

Safety Tips for Draining Gas from a Generator

Never empty a generator fuel tank while the unit is running or hot. Make sure to drain the fuel in an appropriate fuel container and not on the ground. 

The fuel that generators use to produce power is extremely flammable and can catch fire if fuel spills come in contact with the hot generator engine. Make sure your generator is turned off and cooled completely before draining gas.

Drain the fuel from the generator into an external fuel tank or container to store it for later use. Draining the fuel onto the ground or any water body may lead to an accident and contamination.

How to Drain Gas from Generator?

To drain gas from an inverter generator, locate the drain line and turn on the fuel valve. Use the pipe that transfers fuel from the tank to the carbonator to drain the fuel in case your generator doesn’t come with a drain line. You can also use an external fuel pump to siphon your generator’s fuel tank.

The first thing to make sure of before draining a generator’s gas tank is that the generator is not running and the engine is cooled down.

Now, bring your generator out in the open where you have adequate light (preferably sunlight) and rest it on a hard even surface (concrete floor). Remove the generator’s fuel cap which will air to be sucked in when draining gas.

Inverter Generators

You need to remove the side covers to access the fuel system, which is the case in most inverter generators. Once you get access to the inside, locate the fuel drain line, which happens to be with the carburetor in most inverter generators.

Get a fuel can that is large enough to hold all the fuel from your generator’s fuel tank. Place the generator on a surface that is a bit taller than the gas can you’ll be using to drain the gas into.

Now, with the generator’s drain pipe properly placed inside the fuel container, turn on the fuel valve to start draining the gas. Your fuel should now start draining.

Some inverter generators come with a drain pipe that is attached to the carburetor. For such a generator an additional step to drain fuel from the tank is to loosen the drain screw that is located in the carburetor (the above video explains).

Non-Inverter or Open-Frame Generators

Accessing the fuel lines and the carburetor is easy in non-inverter generators as most don’t come with side covers. However, most even don’t come with a fuel drain line.

For generators that don’t come with a dedicated fuel drain line, you can either use the carburetor or the fuel line that brings gas from the tank to the carburetor to drain the gas.

With the fuel valve in the off position, remove the clip on the fuel line that is connected to the carburetor. Place the pipe in a fuel container that is big enough to hold all the gas in your tank.

Now, turn on the fuel valve and wait for your generator’s fuel tank to empty. Once all the gas has drained out into the fuel container, attach the fuel pipe the same way you removed it.

You can also use the carburetor drain to siphon out the fuel from your generator fuel tank if you don’t like the idea of detaching the fuel line. All you have to do is locate the drain screw on the carburetor and loosen it until gas starts flowing out.

However, draining gas through your carburetor means you need a funnel to reach the carburetor bowel as it sits inside the generator frame.

Additionally, you can also use an external fuel transfer pump to siphon the gas out of your generator. Just put one end of the pump into the fuel tank of your generator and the other in the gas container and start the pump. The fuel will move from the generator to the storage container.

Here are two excellent external fuel transfer pumps one is automatic, and the other is handheld.

Irrespective of the type of generator you’re draining, make sure you wipe off any spilled fuel and fasten the fuel lines or carburetor screws properly.

What is the Easiest Way to Drain a Gas Tank?

Letting your engine burn through the fuel and running your tank dry is the easiest way to drain gas from your generator. This is also the safest way as you don’t have to deal with fuel lines, the highly flammable gasoline, and the hazards related to it.

For most non-techies, removing a generator’s side cover, fuel line, or unscrewing the carburetor drain screw can be overwhelming. For such generator owners, running the generator until the unit runs out of gas is the easiest and safest bet.

You can easily run the unit dry when you’re out boondocking by just powering your RV with the generator. All you have to do is to fill up the tank enough to run all your appliances throughout the drying process.

Once the unit starves and dies, let it cool down before storing it on the back of your truck or RV.

How to Drain your Generator Carburetor?

Locate the drain screw on the carburetor and loosen it till gas starts flowing out of it. Place a fuel container with a funnel to store the drained gas.

The main purpose of draining a generator’s fuel tank is to prevent fuel-related issues when in storage. However, draining the fuel tank only solves part of the problem.

To make sure your generator starts right up at the beginning of the next camping season, you need to run the carburetor dry before storing it. This is because gasoline oxidizes and, over time leaves a gummy residue.

As the carburetor is a confined space, the gum settles and clogs the inside which restricts fuel and airflow to the engine. To prevent your carburetor from clogging, make sure you run the engine after you have drained the fuel tank through the fuel or drain line.

As the engine runs, any fuel that is left in the carburetor will be used by the engine, drying your carburetor. However, you don’t have to go through this step if you’re planning to run your generator dry as a method to drain fuel.

Should you Store or Discard the Drained Fuel from the Generator?

You should store the drained fuel for later use if the fuel is still fresh. However, if the fuel is bad, make sure not to discard it on the ground, drainage system, or any other water body.

Once you have drained your generator fuel in a container, make sure to check the condition of the fuel before storing it. If the generator was last run a day or two back, then the fuel is fresh.

All you have to do to keep the fuel from degrading at this point is add the right fuel stabilizer to your storage container. The amount of fuel stabilizer you should use depends on factors like the type of gas and the brand of stabilizer you have.

On the other hand, if the drained fuel is degraded it will have a cloudy or dark texture and have a sour smell to it. In such a case you’ll need to discard the fuel as adding a fuel stabilizer won’t work.

However, you can’t just dump fuel anywhere you like as the liquid is still flammable and toxic. You need to contact your local fire department, and they will guide you to the appropriate dumping station.


Draining gas from your generator before storing is one of the safest ways to keep your unit trouble-free in storage. It will prevent fuel-related issues that will prevent your generator from starting or worse, force you to expensive maintenance or repair.

If you’re a bit technical, you can drain your generator using the drain line or the fuel pipe. Additionally, you can also use an external fuel transfer pump which is easier compared to the previous method.

However, the easiest method to drain gas from a generator is to power it until the unit runs out of gas. This way you don’t have to deal with fuel or removing fuel lines, removing all risk factors.