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Follow up question: removing bad gas from vehicle parked several years

In a previous thread, I got excellent suggestions on removing bad gas from a Dodge minivan which has been sitting at least 4 years. ok4450 suggested removing the schrader valve on the fuel rail, and pumping the old fuel out into a suitable container. Caddyman added smelling the fuel, and checking color, then draining as much as possible, replacing filter……

When I thought of the filter, I wondered if that provides a better way to drain the tank…would it SIPHON out of the tank from there? Seems I’ve had to stopper the fuel line right there when changing a filter on my current Caravan. Wouldn’t some or all the fuel forward of the filter drain back as well?

Otherwise, if siphoning from the fill opening, any suggestions on specifics of starting the flow without sucking on the tubing? I’ve done that long ago, once was enough. I’ve seen a simple device for siphoning at Autozone, a sort of squeeze / pump thing. The clerk told me it was real slow, but I’d like to empty as much as possible manually before introducing electricity and sparks. Any additional tricks worth trying?

I figure that I’d get as much out of the tank as possible, then move on to pumping residual out at the fuel rail as ok4450 suggested.

Barkydog mentioned starting fluid, which I have, but don’t know how I might get it into a fuel injection system.

Last…a safety question…is there a potential hazard from sparks when jumping the fuel pump relay (ok4450’s suggestion) in the vicinity of the hose and gas container attached to the fuel rail? An explosion and fire might ruin the whole afternoon.

Just want to be armed with as many good ideas as possible when I dive into this. Thanks for the helpful ideas so far.

There’s always an inherent danger when working with fuel. Many years ago the fuel trucks at the local AFB used to have nylon seat covers. Anytime a driver would hop out there would be a static discharge crack…

I’ve done this quite a few times without a problem but would recommend extra care while doing so. No electrical widgets around, preferably outdoors, and no smoking of course.

What I do is run a long (7 foot or so) piece of fuel line from the fuel rail test port (Schrader valve removed) into a gasoline jug which I locate on the ground and away from any jumper leads. Make sure the hose fits snugly into the spout of the container and even wrap a rag around it to hold down any fumes.
And of course, keep an eye on the line and make sure there no leaks. With a good pump a tank can be emptied pretty quickly.

I’m not keen on siphoning and with most vehicles it’s impossible, or near impossible to do, due to the design of the filler neck. The SAABs I’ve owned even have a fairly fine mesh grate at the tank and one would be lucky to even stick a toothpick through one of the openings, much less a siphon hose. Hope that helps.

Remove the fuel filter. To start the siphon going you can also put a tube as far as you can in the filler neck. Then pack a rag around it sealing the filler neck as tightly as possible. Then blow art into the hose in the filler, this will raise the pressure in the tank, even if only slightly, and will push fuel out the removed filter line.

With the filter disconnected, you can then jump the pump relay and the fuel will pump out at that point…

You will find that disposing of that old fuel can be a problem…The glib answer of “take it to a recycling center” seldom is that easy…NOBODY wants the stuff. 'Pour it in a shallow pan and let it evaporate is a common answer…

I think you’re over-thinking this problem. I would use a cheap siphon pump to pump as much fuel out of the tank as possible, and I’d do it through the fuel filler neck, not the fuel rail or the fuel filter. Then I would fill the tank up with fresh gas, making the ratio of fresh gas to old gas as high as possible. That mixture of old and new fuel should be good enough to get the car going.

I must object to Caddyman’s idea to let the fuel evaporate. Gasoline fumes are a pollutant, and they are very bad for the ozone layer. Improvement in fuel fume capturing systems have done a lot to help repair the hole in the ozone layer.

That’s what they tell you to do with oil-based paints…

Disposal is not a problem…we have a good haz mat facility here, and proper disposal is a priority for me too. Thanks all for the helpful suggestions! I’ll begin the effort on Saturday afternoon…figure that anything can happen from starting easily to finding a dead fuel pump, or starting but being immobile due to dead transmission. I’m really curious which it will be, or more likely - none of the above.