This strategy will decrease the amount of pumping and draining you have to do, and leaves you with less gas to store or dispose of. Never run a car if you have the wrong fuel in the tank. Draining a full tank will take a long time, but it is not impossible.
You’ll need six feet or so of small ⅜ inch hose, as well as a pump to draw the fuel out. The old trick of sticking a hose in the gas tank then sucking out the gas with your mouth is hazardous to your health and incredibly dangerous. You could swallow gasoline or spill enough to create a serious fire hazard. Have a fire extinguisher specifically for gas fires nearby in case of a fire. Some vehicles have saddle-type fuel tanks and may require a specialized way of removing the fuel from both sides of the tanks. Seek a professional’s help or advice to get all the fuel out.
Take a separate, smaller tube that is rigid and resists kinking. Force this tube down until it hits the blockage, then twist, push, and force the tube around the metal bulb blocking entry to the tank. If a reasonable amount of force doesn’t succeed, do not continue, as you may puncture the filler tube or cause other damage. Take your larger tube, the one connected to the pump, and slip it over the smaller tube.
If you don’t have a pump, but you have a spare tube, stick that in as well. Then, blow into this spare tube, pushing air into the tank, which will then force the gas out of your other tube.
Check the Yellow Pages under Environmental and Ecological Services and Oils, Waste. If you plan on reusing the fuel after the repairs are done, make sure you are storing the fuel in approved fuel containers. You may have to pay to dispose of the gas.
Some vehicles have a fuel test port under the hood to which a fuel tester can be attached and drain the fuel with the special tool. This will require turning on the fuel pump while the engine is not running by jumping the fuel pump relay or using a scan tool.
It is very, very hard to plug the tank back up while it is draining, so don’t plan on stopping until the job is done.
This plug is simply a small bolt screwed directly into the tank. Opening it simply creates a hole for gas to drain out. You usually need a spanner or socket wrench to remove it. However, not all vehicles will have this drain plug. If you see the fuel lines, which are small, removable hoses underneath the tank, you can use these as well. However, you must turn the car on and off, repeatedly, to force the gas out of the tank, as it uses the electric fuel pump to to all the work.
Make sure to have more than enough drain pans to catch all the drained fuel and to make sure no fuel is spilled onto the ground.
The introduction of ethanol into the gas supply has greatly reduced the life-span of gasoline. It degrades much faster, meaning you need to be extra vigilant about draining the fuel if the car hasn’t run in a long time. [2] X Trustworthy Source Consumer Reports Nonprofit organization dedicated to consumer advocacy and product testing Go to source
You must also drain the gas to replace the fuel gauge sending unit.
