Drain Gasoline From A Gas Tank

Draining gasoline from vehicles poses a difficult process for many, and a few different techniques are available for doing so. Due to rampant theft of fuel from vehicles via siphoning, most modern automobile manufacturers have begun installing anti-siphon grids, where the fuel fill neck connects to the fuel tank itself which prohibits insertion of a siphon hose down through the fill neck and into the tank. Car owners must try at least a couple of different methods in an attempt to get fuel drained from the tank.


1. Consult your automobile owner’s manual and, using the Table of Contents, locate information about features related to your fuel system. Using the manual, determine whether or not your vehicle has an anti-siphon mechanism in the fuel fill neck. If the anti-siphon feature exists, check the manual to see if there is a through-the-trunk access compartment under the carpet of your trunk, or any other access to the top of your fuel tank. If your vehicle is an older model, you may be able to siphon the fuel from the fuel tank using a standard siphoning system as mentioned above. Otherwise, please refer to the steps below.

2. Remove the fuel fill cap from your vehicle’s fuel fill neck and insert a siphon hose, feeding it down the fill neck until six feet of hose has been inserted. Place a federally approved fuel container on the ground under the fuel fill compartment and insert the other end of your siphon hose into the fuel container. Pump the hand-operated siphon valve, or activate the pump if electrically powered, and fill the container until completely full. Screw the lid on tight and store in a cool location until needed. Use as many fuel containers as necessary until the vehicle’s fuel tank has been completely emptied.

3. Disconnect both battery cables from your vehicle’s battery using a properly sized socket wrench and socket. Once loosened, lift them off of the battery posts and lay them off to the side of the battery to prevent them from coming into contact with the battery posts.

4. Open your trunk and clear out any items which may be sitting on the floor. Lift up the carpet and scan the metal surface of the trunk floor for a round or a square access door. If your vehicle is so equipped, this door will provide access to the top of your fuel tank. Lift open the access hatch door to expose the top of the fuel tank.

5. Analyze the circular fuel pump assembly mount on the top of the fuel tank. There should be a fuel supply line, a fuel return line and a vacuum pitot valve all connected to the round cover. Disconnect all lines and electric wiring connectors from the sockets and then remove any screws which may secure the circular mount to the fuel tank.

6. Locate the slip grooves on the circular mount, as most of these are designed to have the inside steel plate rotated until the tabs are lined up with rectangular notches, which will facilitate the lifting of the center steel plate and the fuel pump assembly out of the tank. Lift gently and avoid jarring the fuel pump against the sides of the opening when removing. Lay the entire assembly on the metal floor next to the opening.

7. Place a federally approved five-gallon fuel container on the ground beside the vehicle and insert the long end of the siphon tube through the opening of the fuel tank until the end touches the bottom of the tank. Stretch the remaining length over the side of the vehicle so the tip of the other end is inside of the fuel container. Operate the hand pump bulb or turn the electric siphon pump on and fill as many containers as necessary until the fuel tank is completely empty.

8. Place the fuel pump assembly back into the tank, lining the center plate tabs with the rectangular grooves on the plate receptacle cut out. Turn the center plate clockwise to lock it into place in the mount groove and reconnect the fuel lines and electrical connectors. Wipe up any fuel leakages from the metal flooring and allow to dry before unfolding the trunk carpet back over the floor. Reconnect the battery terminals to the battery posts in completion of the task.

9. Consult with an authorized service center if there are no access hatches to the top of your tank, and the fill neck also contains an anti-siphon device. Such vehicles require complete removal of the fuel tank from under the vehicle so the fuel may be removed. Removal of a fuel tank full of fuel isn’t a safe one-person, owner-maintenance task.