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Can anyone recommend a good siphon for getting gas out of a car/truck tank?

My best siphon method is to get the biggest hose that I have that will fit in the
opening and jam it in the tank. Once the hose is in as far as it will go, I put air
pressure in the tank with a blow gun and the fuel will flow. The pressure makes
the gas come out a lot faster, even with only 20 psi or so.

GM

I bought a little $5 pump that you chuck up in a drill and has two threaded connections for garden hose. When it works, it's great. It just doesn't always work, and I'm not sure why.

-Dave

GMJohnny wrote:My best siphon method is to get the biggest hose that I have that will fit in the
opening and jam it in the tank. Once the hose is in as far as it will go, I put air
pressure in the tank with a blow gun and the fuel will flow. The pressure makes
the gas come out a lot faster, even with only 20 psi or so.

GM

Thanks for the suggestion. I was thinking of that but will it work on modern tanks that have vapors vented to a charcoal canister? Would the pressure just scoot out the vent? Guess I could try it and find out. But, I wouldn't put 20 PSI in the tank. There are a lot of square inches on the top and bottom of a tank. Think that might blow the tank apart.

TireSmoker wrote:I bought a little $5 pump that you chuck up in a drill and has two threaded connections for garden hose. When it works, it's great. It just doesn't always work, and I'm not sure why.

-Dave

Would that be a priming issue? Some comments on siphoning devices mention the need for priming.

GM[/quote]
I was thinking of that but will it work on modern tanks that have vapors vented to a charcoal canister? Would the pressure just scoot out the vent? Guess I could try it and find out. [/quote]

Having investigated and worked on an evap system lately, I would be wary of pressurizing a gas tank. I've read that sometimes gas vapors can saturate the charcoal canister. Once this happens, the whole balance of this complex system is messed up. It could result in trouble codes and worst case you might be required to replace the canister (big bucks). Just my 2 cents.

I could run a hose thru a spare gas cap down into the tank, disconnect the hose from the canister and use that hose to pressurize the tank. There's gotta be a good way to do this.

Reason I'm looking for a good siphon is I'd rather fill the vehicle tanks and use that, if its needed, as a supply for the generator rather than filling gas cans and, nine times out of ten, not using the generator and emptying the cans into fuel tanks. Looks like that's what I'll be doing with the cans of gas I got yesterday.

WXO found this thread which is right on topic. http://www.gm-trucks.com/forums/topic/1 ... generator/

Put a petcock on the gas tank then you can drain the gas into a generator any time you want. That would take some work to set up the first time but I'm sure it would be less work than restoring a Maverick. Just don't put it any place too obvious or someone else will help themselves to your gas. Or you could put it in the fuel line somewhere (think on the return line from the fuel injector rail) and let the fuel pump move the gas for you.

Siphoning in modern tanks is not an easy task. Don't some of them have screens at the bottom of the filler neck to prevent that?

I had assumed that your tank was not in a car and you were just trying
to drain it...... How about disconnecting the fuel line somewhere after the
fuel pump and using the fuel pump to pump the fuel into a can....

GM

Think it will be one of two solutions.

1. Remove the Schrader valve core from the fuel rail, attach a hose, jumper the fuel pump 12V in and use the fuel pump to fill the gas can. The fuel pump has to have a jumper because the computer will only power the fuel pump for a few seconds unless engine starts and with the Schrader valve removed there probably wouldn't be enough pressure at the injectors to run the engine. This method might be too slow.

2. Remove the fuel tank filler tube and eliminate whatever anti-siphon device is in there. Then get one of these tdj3v-4331054102@sale.craigslist.org or one of these http://www.amazon.com/Piece-3-5GPM-Shak ... B00CRPAHKE This method requires more mods to the vehicles so might not get done before the next threatened power outage.

Thanks everyone for thoughts and comments.