KLC Lewis wrote:
"That raises another question. Every year at winterizing time, Essie
gets some stabilizer of some type or another added to her diesel fuel.
This is the same fuel every year, as Essie just sips the stuff daintily
and would never even dream of guzzling. So the question is, does the
stabilizer evaporate or otherwise dissipate during the course of the
year, or does it "build up" in the fuel?"

The "stabilizer" stays in the fuel, but usually will never reach
concentrations that would do any harm. But there are other factors in
fuel that degrade over time so it is a good idea to replace fuel that is
more than two to three years old, according to a few engine 'experts'
I've read articles by, including those at Mack Boring - the importers
for Yanmar.

And this brings up another point. Several diesel engine 'experts' I've
read recommend never using the same biocide more than two seasons in a
row, due to the microbe's penchant for becoming *immune* to that
particular biocide. So it is recommended to change type of biocide
periodically. If using biocide, make sure you don't use too much, or
keep adding it over time to the same fuel - some brands will precipitate
hard abrasive solids out into the fuel if in too high concentrations,
which could clog filters or harm engines if passed by filters. We're
talking only capfuls here.
Please don't ask for cites, it'll take months of re-reading to find
them! I'm just going by the notes I took.

Red