How To Drain ATV Fuel – Your Complete Guide For Safe Storage

We’ve all been there. After a long winter, you pull the cover off your ATV, excited for the first ride of the season. You turn the key, hit the starter, and… nothing. Just the sad whir of an engine that won’t catch. Nine times out of ten, the culprit is old, stale fuel that has gummed up your carburetor or fuel system.

We promise this comprehensive guide will show you exactly how to drain ATV fuel the right way, saving you from future frustration and expensive repair bills. This isn’t just about dumping gas; it’s about preserving your machine’s performance and ensuring it starts reliably every single time.

In this article, you’ll learn the critical reasons for draining fuel, the essential safety precautions, three foolproof methods for getting the job done, and what to do with the old gas afterward. Let’s get your quad prepped and ready to ride.

Why Draining Your ATV’s Fuel is a Non-Negotiable Maintenance Task

Leaving fuel in your ATV for extended periods is one of the quickest ways to cause problems. Understanding the “why” behind this task is the first step in a solid how to drain ATV fuel care guide. It’s about being proactive, not reactive.

Modern gasoline, especially fuel containing ethanol, begins to break down in as little as 30 days. This degradation process is the root cause of many performance issues. The benefits of how to drain ATV fuel are clear: you prevent costly damage and ensure your machine is always ready for the trail.

Here’s what happens when fuel goes bad:

Varnish and Gum Buildup: As gasoline evaporates, it leaves behind a sticky, varnish-like residue. This gunk can clog the tiny passages in your carburetor’s jets or foul your fuel injectors, leading to poor engine performance, hard starting, or a no-start condition.
Ethanol and Water Contamination: Ethanol is hygroscopic, meaning it attracts and absorbs water from the atmosphere. This water can lead to corrosion inside your fuel tank and engine components. In winter, this water can freeze, blocking fuel lines entirely.
Phase Separation: Over time, the ethanol-and-water mixture can separate from the gasoline, sinking to the bottom of your tank. If this sludge gets sucked into your engine, it can cause significant running issues and potential damage.

Draining the fuel before long-term storage (more than a month) is the single best way to ensure a clean, healthy fuel system when you’re ready to ride again.

Safety First: Gearing Up for a Safe Fuel Draining Job

Before you even think about opening a fuel cap, we need to talk about safety. Gasoline is highly flammable, and its vapors are explosive. This isn’t the time to cut corners. Treating this job with respect is the most important of all our how to drain ATV fuel tips.

Never work in an enclosed space like a basement or an attached garage with a gas water heater or furnace. Fumes can travel and find an ignition source with disastrous results.

Essential Safety Gear You Can’t Skip

This is your non-negotiable personal protective equipment (PPE). Don’t start the job without it.

Chemical-Resistant Gloves: Standard latex gloves will dissolve. Use nitrile gloves to protect your skin from gasoline.
Safety Glasses: A splash of fuel in the eye is a serious medical emergency. Always wear wrap-around safety glasses or goggles.
Fire Extinguisher: Keep a Class B (rated for flammable liquids) fire extinguisher within arm’s reach. Know how to use it.

Setting Up Your Workspace

Your environment is just as important as your gear. A safe setup minimizes risk.

Ventilation is Key: The absolute best place to do this is outside, away from direct sunlight. If you must work in a garage, ensure the doors are wide open for maximum airflow.
No Ignition Sources: This is critical. Make sure there are no open flames, pilot lights, sparks, or active electrical equipment nearby. This includes water heaters, furnaces, and even plugging in a shop light.
Stable Ground: Work on a level surface to prevent your ATV or fuel container from tipping over.

Tools & Supplies Checklist

Having everything ready before you start prevents running around mid-job.

An approved fuel container (clearly marked for gasoline) with enough capacity for your entire tank.
A fluid transfer or siphon pump (manual or battery-powered).
A set of basic hand tools (screwdrivers, pliers, and wrenches).
A drip pan to catch any spills.
Plenty of clean rags or shop towels.

The Complete How to Drain ATV Fuel Guide: 3 Proven Methods

Alright, with your safety prep done, it’s time to get that old fuel out. We’ll cover three effective methods, from easiest to most thorough. This section is the core of our how to how to drain ATV fuel instructions. Choose the method that best suits your ATV and your comfort level.

Method 1: The Siphon Pump (The Easiest & Most Common Way)

Using a siphon is the most straightforward way to empty the majority of the fuel tank. Avoid the dangerous old-school method of using your mouth; a cheap hand pump is a much safer investment.

Position Your Container: Place your approved fuel can on the ground next to the ATV. It needs to be lower than the fuel tank for gravity to help the siphon work effectively.
Insert the Hose: Feed the “in” hose of your siphon pump into the ATV’s fuel tank, pushing it down until you feel it hit the bottom.
Start the Siphon: Place the “out” hose securely into the fuel container. Begin pumping the siphon bulb or handle. Once the fuel starts flowing, gravity will take over.
Monitor the Flow: Keep an eye on the process to prevent overfilling your container. You may need to adjust the hose in the tank to get the last remaining bits of fuel out.

A pro tip is to use a pump with a semi-rigid intake hose, which is easier to guide to the lowest point in the tank.

Method 2: Using the Fuel Petcock (For Carbureted ATVs)

If you have a carbureted ATV, the fuel petcock (the valve on the side or bottom of your tank with ON/OFF/RES settings) offers a direct way to drain the tank and line.

Locate the Petcock and Fuel Line: Find the fuel petcock and trace the fuel line from it to the carburetor.
Prepare to Catch Fuel: Turn the petcock to the OFF position. Place your drip pan or a small container under the carburetor.
Disconnect the Fuel Line: Using pliers, slide the spring clamp off the fuel line where it connects to the carburetor inlet. Gently twist and pull the hose off the nipple. Be ready for a small amount of fuel to spill out.
Drain the Tank: Direct the end of the fuel line into your approved gas can. Turn the petcock to ON. Fuel will begin to flow out. Once it stops, switch it to RES (Reserve) to drain the rest.
Reconnect: Once empty, turn the petcock back to OFF, re-attach the fuel line to the carburetor, and secure the clamp.

Method 3: Draining the Carburetor Float Bowl (The Final, Critical Step)

This is one of the most overlooked but important common problems with how to drain ATV fuel—people drain the tank but forget the carb! The small amount of fuel left in the carburetor’s float bowl is the most likely to gum up the jets.

Locate the Drain Screw: Look at the very bottom of your carburetor. You will see a small bowl (the float bowl) with a single screw or bolt on its lowest point. This is the drain screw.
Position a Rag: Place a rag or a small cup directly underneath the screw to catch the fuel, which will only be a few ounces.
Loosen the Screw: Using the correct size screwdriver or wrench, slowly turn the drain screw counter-clockwise. You only need to loosen it a turn or two; you don’t need to remove it completely.
Drain and Tighten: Fuel will begin to dribble out. Once it stops, gently snug the screw back up. Do not over-tighten it, as these screws are often made of soft brass and can strip easily.

Beyond the Drain: What to Do After the Fuel is Out

Getting the liquid fuel out is step one. For truly bulletproof storage, there are a couple more things to consider to ensure every last drop is gone from the system.

Running the Engine Dry (The Final Purge)

After you’ve drained the tank and the carburetor bowl, there’s still a tiny bit of fuel in the lines and internal passages. The best way to clear this is to burn it off.

Reconnect your fuel line, leave the tank empty, and try to start the engine. It should fire up and run for a few seconds or up to a minute before it sputters and dies. Once it does, the system is as dry as it can get.

The Great Debate: Drain Dry vs. Stabilized Full Tank

You’ll hear two main strategies for long-term storage. Both have merit.

Drain Dry Method (Our Recommendation): This involves following all the steps above. Its main advantage is that there is zero fuel in the system to go bad, attract water, or cause issues. It’s the most foolproof method.
Stabilized Full Tank Method: This involves filling the tank to the brim with fresh, ethanol-free gasoline and adding a high-quality fuel stabilizer. A full tank prevents condensation and rust. This is a good option for EFI (fuel-injected) ATVs where draining the system is more complex, or for storage periods of only 2-4 months.

Eco-Friendly Fuel Disposal: Best Practices for Old Gas

You’ve successfully drained the fuel. Now what? Proper disposal is your responsibility. Following a sustainable how to drain ATV fuel process protects the environment and is often required by law.

DO NOT pour old gasoline down a drain, onto the ground, or put it in your household trash. It is considered hazardous waste.

Here are your safe and eco-friendly how to drain ATV fuel disposal options:

Local Hazardous Waste Facility: Most municipalities have a household hazardous waste (HHW) collection site that accepts old gasoline free of charge. A quick search for “[Your City] hazardous waste disposal” will give you locations and hours.
Auto Repair Shops: Some local mechanic shops will accept small quantities of used fuel, as they often have services that collect their hazardous fluids. Call ahead to ask.
Dilution (Use with Caution): If the fuel is less than 6 months old and looks/smells okay, you can often dilute it by pouring the small amount from your ATV into a nearly full car or truck gas tank. The large volume of fresh fuel will make the old gas negligible. Do not do this if the fuel is very old, dark, or has water/debris in it.

Frequently Asked Questions About Draining ATV Fuel

How often should I drain my ATV fuel?

You should drain the fuel any time you plan to store your ATV for more than 30-60 days. For many riders, this means doing it once at the beginning of winter. It’s one of the most important how to drain ATV fuel best practices for seasonal storage.

Can I just use a fuel stabilizer instead of draining the tank?

For short-term storage (1-3 months), a good fuel stabilizer in a full tank of fresh, ethanol-free gas is often sufficient. For longer-term storage, or if you’re using ethanol-blended fuel, draining the system completely is the safest and most reliable method to prevent problems.

What’s the difference between draining a carbureted vs. a fuel-injected (EFI) ATV?

The process of siphoning the tank is identical. The main difference is that EFI systems don’t have a carburetor with a float bowl to drain. For an EFI machine, the best practice for storage is to fill the tank completely with fresh, stabilized, ethanol-free fuel and run the engine for 5-10 minutes to circulate it through the entire system.

What are the signs of bad fuel in my ATV?

The classic symptoms of old, degraded fuel include difficulty starting, a rough idle, stalling, sputtering when you give it gas, a loss of power, and a “sour” or varnish-like smell from the exhaust or gas tank.

Mastering how to drain ATV fuel is a fundamental skill for any owner. It’s a simple, proactive step that pays huge dividends in reliability and performance. By taking an hour to do this job correctly before storage, you’re guaranteeing a quick-starting, smooth-running machine for your next adventure.

Now you have the expert knowledge and the step-by-step plan. Be safe, be thorough, and keep that quad ready to conquer the trails. Ride on!

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Thomas Corle

Founder & Automobile expert at FatBoysOffroad

Automobile expert and off-road enthusiast, sharing in-depth knowledge of vehicles, gear, and adventures. Helping readers make smart decisions and enjoy the thrill of off-roading safely and confidently.