How to siphon gas out of newer cars

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Have you ever needed some gas for your lawnmower, motorcycle, generator or perhaps tried to help a stranded friend who needed some gas, assuming you could easily get it out of your own vehicle? If you have, you know it’s not possible to siphon gas with conventional tools or standard siphons available on the market today.

Many people have tried to siphon gas out of one of their newer vehicles only to find out they hit one if not two major difficulties. It is not easy. Most newer model cars and SUV’s have emergency valves that stop gas from draining out in the event of a roll-over. This valve also acts as a siphon prevention system which is the reason why nearly all the siphon devices and pumps sold these days are useless. That being said, there is a way to siphon gas from a modern car, you just need to know how to do it and have the right tools for the job.

The anatomy of the blockage in newer vehicles is a ball valve or butterfly valve. There is enough room for gas to get through the fueling tube into the tank, but if the car flips over and gas begins to flow the other direction, the ball moves to the inlet and blocks the gas from escaping or the butterfly flap closes.

The fundamental issue is that you need a line skinny, stiff and flexible enough to get through the valve and around the ball or flap. That is much easier said than done.

The first thing you need to get around a ball valve is 6-8 feet of 1/4 inch stiff plastic line with a smooth tapered tip narrowed towards the end with a semi rigid outer guide line to keep the 1/4 inch line from kinking when it hits the initial ball valve. With a firm twisting, bump and pushing motion, it is reasonably easy to get around most ball valves.

The next thing you’ll need is a thicker diameter fuel line that can receive the 1/4 inch line without leaking. This line will be used to connect to a fuel filter and then to a pump.

Gravity siphoning through the narrow line is doable but extremely slow. With a hand squeeze bulb pump you can move more gas but for best results use a very powerful fuel pump with 7-10PSI and serious self-priming dry-lift capability like the electronic fuel pump that comes with Gas Tapper.

To gravity siphon without getting a mouthful of gas you will not only need a hand squeeze bulb to prime the siphon, but you’ll need (2) inline T-connectors with an on/off valve in the middle. This allows you to prime the lines, get gas flowing, then open the valve to allow gravity to take over. Again, this is not a reliable method to go car-to-car. For the lateral transfers, going distance transferring gas up-hill, you’ll really need a pump. The Gas Tapper comes complete with everything you need to access your gas when you need it.

Pure siphoning through 1/4 inch line with sufficient gravity, you can move approximately 1 gallon every 8 minutes. Without the 1/4 inch line it's about a half gallon a minute.

Moving gas through a 1/4 inch line using a hand squeeze bulb, it is possible to move approximately 1 gallon every 4 minutes (until your hand gives out).

Moving gas through a 1/4 inch line using Gas Tapper 12V moves approximately 0.7 gallons per minute or 1 gallon in 1.2 minutes.

Gravity Siphoning Hand Squeeze Bulb Pump Gas Tapper Pro Edition
1 gallon
8 minutes
1 gallon
4 minutes
1 gallon
1.2 minutes

Being that electronics can fail and it's always a good idea to have a manual override method as well as those folks looking for lower cost peace-of-mind, Gas Tapper is releasing a hand-powered squeeze bulb model with a gravity override valve which does a nice job, just slower. Check for updates.

Happy Gas Tapping...

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