How to Remove Gas from the Fuel Tank

It is often necessary to drain the fuel from a car’s gas tank in some of the following situations:

  • If you run out of gas while far away from a gas station, you may want to siphon gas from another vehicle into yours.

  • You may want to drain out the fuel before storing a car away for winter.

  • You may want to transfer fuel from one vehicle to another vehicle at home.

  • Fuel in the tank may have been contaminated and must be removed before refilling the tank.

person using mouth to siphon

  • Warning: There are many dangers associated with manually siphoning gas.

The most commonly known method of siphoning gas is the most dangerous one. In this method, you had to put a hose in the fuel tank and draw the gas out using your mouth ﹘ understandably, this was not a pleasant experience or a safe procedure by any means. This method is dangerous and is not advisable due to the following reasons:

Reason 1: Inhalation of gasoline fumes. Exposure to gasoline fumes can harm all the major organs in our bodies. Direct inhalation of the fumes can damage your lungs and cause carbon monoxide poisoning.

Reason 2: Can cause loss of consciousness in risky situations. Breathing in gas vapours can cause dizziness, fainting and in extreme cases, brain damage. Using this method when you are alone on the side of a highway or away from medical attention is very dangerous.

Reason 3: Risk of swallowing gasoline. Gasoline will probably get into your mouth using this method. Gasoline is toxic to ingest. Gasoline poisoning is extremely dangerous and requires emergency medical attention.

Reason 4: Risk of fire. It is extremely dangerous to siphon gas or handle fuels next to open flames or where people are smoking. It is of utmost importance that you take the correct safety precautions before doing so.

  • Warning: This method is extremely risky and dangerous. The only reason to use this method would be if the situation were extremely pressing and there was no time for a better solution, or if the length of tube available to use is not sufficient to cut into two.

It is important to know how to siphon fuel from a gas tank and do it correctly and safely. You can be prepared for any fuel emergency by being aware of the recommended siphoning methods and following them correctly.

It is advisable to keep rubber tubing and a siphon pump in the trunk of your car when traveling long distances so that you will not need to siphon gas using your mouth.

Here are a couple of methods to siphon gas that are safer than using your mouth.

Method 1 of 2: Using two tubes to siphon gas

In this method, two lengths of flexible rubber tubing are used to siphon gas into a fuel-safe container. A gas can works well as a fuel-safe container because it can be closed and won’t allow the fuel vapors to escape.

  • Warning: Gasoline vapors are explosive and hazardous to breathe.

  • Tip: Use clear tubing to make it easier to monitor the flow of gas.

Materials Needed

  • Gas can
  • Air pump or small air compressor
  • 6 to 12 feet of rubber tubing (1/4” to 3/8” diameter)
  • Rag or soft cloth material

Once you have the required materials, here’s how it’s done:

Step 1: Connect the longer tube. Take two lengths of tubing - one longer than the other. Take the longer tube and connect one end to the gas tank and the other to the fuel container.

Step 2: Connect the shorter tube. Hold one end of the shorter tube in your hand while putting the other end in the fuel tank beside the longer tube.

rag packed into fuel tank

Step 3: Seal the fuel filler neck. Find a rag or any other soft material to fill in the space around the tubes in the fuel filler neck and create a seal. This will help keep the pressure that was created by blowing air into the tank from escaping around the tubes.

person blowing into tube

Step 4: Blow air into the shorter hose. Force air into the free end of the shorter hose, either with a low pressure air pump, or by blowing air in with your mouth.

  • Warning: Do not use a high pressure pump or the fuel may come out of the tank in large amounts and cause fuel tank and system damage.

thumb covering shorter end of tube

  • Warning: If you are using your mouth, be careful not to inhale from the tube. Use your thumb to cover the end of the hose as soon as you stop exhaling to prevent the fumes from entering your lungs.

The low pressure should push gas out of the other tube and into the container.

Step 5: Stop forcing air into the hose. Once the fuel is flowing, no more pressure is needed. The fuel will continue to flow unless the hose is kinked, or the tube is removed from the fuel tank.

Step 6: Remove the tubes. Remove both tubes from the gas tank when you’re finished, and don’t forget to put the gas cap back on before driving.

Method 2 of 2: Using a siphon pump

It is useful to keep a siphon pump in the trunk of your car if do a lot of travelling in rural areas or if you live far away from a gas station. It is also a handy tool for a home garage.

Here’s how you can use a siphon pump to remove gas from a fuel tank:

Materials Needed

Step 1: Prepare to siphon the gas. Get a fuel-safe container to pump the gas into and remove the gas cap of the vehicle.

siphon pump connected to gas tank and fuel container

Step 2: Understand the workings of the pump. Each end of the siphon pump has a tube coming out. Look at the markings on the pump to find the tube that must be placed in the gas tank. Read any instructions that came with the siphon pump.

  • Tip: Some pumps may have a handle like a bike pump, while others just have a squeezable plastic or rubber bulb. You can also use electric or battery operated gas siphon pumps to transfer the fuel.

Step 3: Connect the tubes. Place one tube in the fuel tank and the other tube in the fuel-safe can.

Step 4: Squeeze the bulb. Squeeze the bulb a few times, to start the siphon action. You can stop squeezing the bulb when the gas starts flowing. The gas should flow through the tubing until the tubing is kinked or the tube is removed from the gas tank. Continue transferring the fuel till you have the desired amount.

Step 5: Take the pumping tube out of the fuel tank. Replace the gas cap after you finish.

Get a certified mechanic to take a look at your car if you find that the fuel tank is leaking or if the fuel door is not opening and closing correctly.


Next Step

Schedule Check Fuel System

The most popular service booked by readers of this article is Check Fuel System. YourMechanic’s technicians bring the dealership to you by performing this job at your home or office 7-days a week between 7AM-9PM. We currently cover over 2,000 cities and have 100k+ 5-star reviews... LEARN MORE

SEE PRICING & SCHEDULING

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Recent Check Fuel System reviews

Excellent Rating

(10)

Rating Summary
9
0
0
0
1
9
0
0
0
1

Steven

14 years of experience
425 reviews
Steven
14 years of experience
Chrysler Town & Country V6-3.8L - Check Fuel System - Avondale, Arizona

Joe

15 years of experience
453 reviews
Joe
15 years of experience
Toyota Pickup L4-2.4L - Check Fuel System - Brentwood, Tennessee
I was very impressed with Joe. I would recommend Joe to all my friends.

Chris

15 years of experience
312 reviews
Chris
15 years of experience
Land Rover Range Rover V8-4.0L - Check Fuel System - Poway, California
Chris was able to solve my problem and seem very knowledgeable of how to repair my car.

Long

22 years of experience
32 reviews
Long
22 years of experience
Mercedes-Benz C230 L4-2.3L Turbo - Check Fuel System - Sacramento, California

Need Help With Your Car?

Our certified mobile mechanics make house calls in over 2,000 U.S. cities. Fast, free online quotes for your car repair.

GET A QUOTE

Related articles

How to Pump Gas the Right Way
Locating your fuel filler, pre-paying for fuel, choosing the correct fuel grade, and not topping off are helpful tips to pump fuel like a pro.
How to Make Ethanol Fuel
Ethanol fuel is an alcohol-based type of biofuel (https://www.yourmechanic.com/article/5-essential-things-to-know-about-biofuel) that is used as a popular alternative to gasoline. It is made from distilled plant and biodegradable materials, such as corn and sugar, as opposed to regular gasoline, which is made...
How to Replace a Fuel Filler Neck
The filler neck for the fuel tank fails if there is exterior damage on the neck or if an error code shows that vapors are present.

Related questions

Fuel gauge doesn't work correctly
It sounds like either the gauge itself may have failed or the sending unit for the fuel gauge that is connected to the fuel pump (https://www.yourmechanic.com/article/symptoms-of-a-bad-or-failing-fuel-pump) has failed. On most vehicles there is a floatation device that is connected to...
Fuel gauge is erratic and inaccurate
Hello. Based on the symptoms you are reporting, your supposition is correct. The sending unit is typically a variable resistance element (i.e., a potentiometer) that can be tested by the Mechanic with an ohmmeter. These units can physically bind. The...
Hard startup immediately after fill up with gas. Then starts quickly each time until next fill up.
The most common cause of hard start after fill up (https://www.yourmechanic.com/services/car-is-hard-to-start-inspection) is going to be the excessive gas fumes during refueling the vehicle will flood the engine causing the hard or no start. The excessive fumes will normally be stored...

How can we help?

Our service team is available 7 days a week, Monday - Friday from 6 AM to 5 PM PST, Saturday - Sunday 7 AM - 4 PM PST.

1 (855) 347-2779 · hi@yourmechanic.com