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Old diesel loses some combustibility properties, and you may need to dispose of it. Unfortunately, disposing of old diesel fuel isn’t an easy process.

Diesel is used in transportation to power farming and construction equipment like garden tools and generators. Leaving diesel unused for a while could lead to contamination or degradation. Damping it down toilets or on land can contaminate water sources, damage property, or even pose a fire hazard.

To dispose of old diesel fuel, you must determine if you can still use it after diluting it with fresh fuel. If not, you’ll need to get in touch with hazardous waste collectors, take it to the disposal center, pay for the disposal service, and find out if they have a limit on the amount they can take.

Most people don’t realize that diesel gets ineffective once it gets old and the only thing to do is dispose of it.

Our detailed guide covers some of the steps you need to dispose of old diesel fuel safely.

Table of Contents

How Long Does Diesel Last?

Diesel can last up to a year when stored under ideal conditions, but on average, you shouldn’t store it for more than six months.

It should be treated with stabilizers when storing diesel fuel and kept under excellent conditions, around 70 degrees Fahrenheit.  Additionally, you should store it in a self-venting container on the ground and not on a shelf.

Easy Steps to Safely Dispose of Old Diesel Fuel

Some of the steps you need to follow while disposing of old fuel include:

1. Check Usability

Start by checking whether the old diesel is contaminated or safe before determining your disposal options. Pour the gasoline into a glass container and another fresh diesel into another container.

Old diesel that smells sour or has a darker than usual color has lost efficacy and needs to be discarded.  Over time, diesel loses its usability if it’s been in storage for a long time, which means it loses combustibility and does not fire up any farm equipment or vehicle.

Although old diesel won’t damage your engine, it can make it harder for your engine to fire or lead to an engine that runs inefficiently.

2. Reuse if the Diesel is Uncontaminated

If the excess gas has signs of discoloration, rust, or dirt, you should dispose it as it could be contaminated. However, if the gasoline still has its usual color and smell, you can still use it by diluting it with new diesel.

Adding the new gasoline increases the entire tank’s combustion ability, but you need to follow the proper proportions. For a half tank or less diesel, fill the remaining half with fresh gasoline to dilute it. That will get the engine firing, and you can add fresh diesel after using half of it.

Diluting large quantities of old diesel can be tricky. Check your gas tank capacity, especially if the old gasoline is in your car’s gas tank. The fuel gauge will tell you how much gasoline is left. If you have ¾ of gasoline left in a small tank, use a pouring spout to add in the old diesel.

3. Look For a Disposal Center

If you dispose of old diesel, you must find the nearest disposal center that accepts old gasoline.

Some recycling centers accept old gasoline and recycle it. They should advise you on how to get the gasoline to the center. A disposal center is another option if you can’t find a recycling center.  Do your research and find out if they have operating hours, what they accept, and if there are any restrictions.

A city management agency or the county would be a great place to begin your search. Alternatively, you can google hazardous waste disposal centers in your area.

Specific disposal centers allow you to bring old gasoline for free if you’re a resident of the area, but outsiders need to pay a disposal fee. You may notice that a few centers have a maximum gas amount they accept from a person or a single visit, while others will be open for a few hours, which is why you should call ahead.

4. Use an Approved Container to Transfer Old Diesel

After confirming that the local disposal center accepts old gasoline, you’ll need to transfer it to the center in an approved container. That can be done on metal or plastic gas airtight containers. Seal the container once you’ve added in your old gas.

Transfer the container to a bin or cooler to prevent it from toppling during transportation.

5. Handle Any Spills Immediately

If you have spilled diesel in your garage, use an absorbent product to soak up the fuel. In case of gasoline spills on your clothes, use a fabric cloth to absorb any liquid.

You can use baking soda on the stained area and brush it to remove gasoline traces. Use hot water and liquid soap to wash the clothes as any gasoline can cause combustion in the dryer.

6. Transport Old Diesel to the Disposal Center

Transport gasoline carefully and ensure the containers are sealed to avoid any leaks. You’ll empty the old has at the disposal center into a storage vessel and carry your container back home.

7. Deliver it to a Fire Station

Some fire stations use diesel to start fires for training purposes. They filter and reuse it.  Get in touch with a local fire department to determine if they would be interested in the old gasoline.

8. Contact the City’s Landfill to See if They Accept Old Diesel

Most city landfills accept uncontaminated diesel fuel. However, you have to take it to the landfill in a spill-proof container and label it as hazardous trash.

Note that some landfills will charge a fee for hazardous waste disposal.

9. Take it to An Auto Repair Shop.

Some auto parts and repair shops accept hazardous fluids, while others only accept transmission fluids. Call the local auto repair shops around and inquire if they accept old diesel and if they have any requirements.

10. Ask Neighbors Around

If all the above options fail, you can ask the people around if they’d be interested in the old gasoline. Those in construction, farming, or fishing may be willing to take uncontaminated fuel.

How To Safely Dispose Of Old Diesel Fuel (10 Easy Steps)

About The Author

Charles Redding

Charles Redding

I've spent many years selling cars, working with auto detailers, mechanics, dealership service teams, quoting and researching car insurance, modding my own cars, and much more.

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