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Water in the gas?

My truck has a nonlocking gas cap. This morning I got a phone message from my building super telling me that the hatch & gas cap were hanging open. It’s been raining on & off since midnight, so I’m concerned that water’s dribbled past the vapor-flapper thing in the gas hole. I’m at work, can’t go look at it, but can water get through that flapper? If so, will it help to get a clean gallon of gas into the tank before I try & drive anywhere? And how do you get water OUT of the tank? THANKS!

Water could leak in. Any way to get some gas-line anti freeze (Heet)? I’d put a couple of bottles of that in. Only way I know to get the water out is to have the tank drained.

If any water got into the tank it is probably a negligible amount. Close it up and drive on.

When I got water in my gas (misconnected the winshield washer line on the Porsche!) my Dad, the chemist, suggested pouring rubbing alcohol into the tank. Like about a 1-pint bottle for a tank some where between half and full (abt 15 gal). There was a LOT of water, so it took a several tank-fulls to disolve it all – but it worked.

Good idea, but gasline antifreeze (essentially the same thing)was designed for this purpose and is a lot cheaper than rubbing alcohol.

THANKS for both the suggestions of Heet/alcohol - yes I can put some in the tank, and drive as usual – but what kind of behavior will I get with wet gas? Sputtering, dying on the highway —? What’s the range, from annoying to dangerous?

The amount that got in should have been extremely negligable. However, if you’d like to put a bottle of drygas in (as already discussed) it’ll do absolutely no harm.

If it helps you sleep better, it’s worth the $2.

Before anyone starts pouring “rubbing alcohol” into his gas tank in order to “dissolve??” the water in the tank, please consider this:

Isopropyl Alcohol comes in two varieties, generally speaking.
There is “70% Isopropyl Alcohol” and there is “91% Isopropyl Alcohol”.
The 70% variety contains–guess what–30% WATER.
If you want to splurge on the 91% variety, it “only” contains 9% WATER.

So, by my calculations, for every pint bottle of 70% alcohol that is added to a tank of gas, you are actually adding almost 5 ounces of water, along with the alcohol. The 91% variety would add about 1.5 ounces of water per pint of alcohol.

If someone wants to eliminate water from his fuel system, why would he add more water to it?

With most gasoline containing 10% ethanol is there really any need to add more?

If it helps you sleep, yes. Not for the car’s sake, for the owner’s.