"Scott Dorsey" > wrote in message
...
> hls > wrote:
>>"Scott Dorsey" > wrote in message news:itvfi1>
>>> Problem is that this is very dependant on the electrodes being used.
>>> If you had a couple standard electrodes, though, you could do it
>>> accurately.
>>
>>I dont think even that would help this method, Scott.
>
> It's true that there's other stuff that will increase conductivity, but I
> think everything that will possibly increase conductivity is going to be
> something you probably don't want in your brake lines.
>
> But, unless you have calibrated electrodes and a calibrated volume,
> you can't get resistivity from resistance.

This is true. Conductivity or resistivity measurements will respond to
various types of contaminants in the brake fluid, to temperature, etc.
But maybe you dont really need a very accurate measurement.

I think it would be cheaper and better just to flush out the old
stuff and replace every couple of years.

I still have that #@& Reatta that has the very special braking system.
If you dont flush that one every couple of years, you get to buy a new
or rebuilt master cylinder, which - last I heard - cost the better part
of a couple of grand.