On Fri, 21 Sep 2001, Olin Lathrop wrote:

> > I'm trying to make a simple fuel level indicator for a fuel tank.  I only
> > need to be able to sense a few levels (i.e. Full, ~1/3 full, Near Empty).
> > I'm thinking of having two wires (or other electrical contact)
> actually -in-
> > the gas, and using the fuel to "close the switch".  I'm pretty sure this
> > would work for water, but I don't know if the gas will be able to conduct
> > electricity well enough.  There is also the ignition issue, but at the
> > voltages I'd use it shouldn't matter.  I will be using 94 Octane gasoline
> > for my purposes.
> >
> > Does anyone have any idea if this would work, or possibly have another
> > suggestion?
>
> I don't know, but if I needed to I'd stick ohm meter probes into a glass of
> gasoline.  I would think that these kinds of hydrocarbons don't conduct
> electricity well for lack of ions, but I have no idea what the effect is
> after all the additives.  But again, it seems like finding out for yourself
> is quicker and more reliable than asking the list.

I seem to recall SCCA track oficials using some sort of resistive testing
to check for illegal fuel additives (or higher levels than allowed), so I
think Olin's point is valid.  On the other hand, that would also mean
you'd have to use the exact same fuel formulation every time -- good luck
with that.  8-P

Dale

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