On Jun 2, 8:05*am, "Elle" <honda.lion...@spamnocox.net> wrote:
> "Bill Putney" <b...@kinez.net> wrote
>
> > *BUT* - again - the fuel is constantly flowing thru and
> > around all internal components of the pump whenever it is
> > running providing cooling (unless you actually run out and
> > the engine stops - but that is a different scenario
> > altogether, and even then, the pump will still be full of
> > fuel at that point with a full column of fuel from its
> > lowest end to the fuel rail - only the pickup will be
> > filled with air, and there won't be any flow - and most
> > cars turn the pump off when the computer senses that the
> > engine is no longer running).
>
> "most"? I would think you would want to err on the side of
> safety and not inconveniencing a driver with a sudden pump
> breakdown.
>
> Barring presentation of a study showing no detrimental
> effects of either regularly running on a very low tank or
> running to empty, I think not doing these things is easy
> enough and indeed an investment that costs one only a litle
> extra time getting gas over the life of the car. If possibly
> burdening the pump by forcing it to move air is not really a
> problem, then I remain concerned about dirt in the bottom of
> the tank clogging the filter and lines downstream of the
> pump prematurely, or possibly wearing mechanical parts on
> the pump, causing the pump to have to work harder, meaning
> it draws more current, aging electrical parts *more quickly,
> etc.
>
> Does rust accumulate in fuel tanks? If so, does running it
> near empty hasten the buildup of rust?
>
> What are the leading causes of fuel pump failure? If it's
> "age," what exactly causes aging to accelerate?
>
> I do not want your speculation. I am well experienced in
> pump design myself. I want facts from a study of pump
> failure.

If you don't mind me breaking in to ask a question?

How hot would the fuel need to become in order to
accelerate the breakdown of the materials used in
the fuel pumps you're familiar with? In my mind I
can't imagine most materials responding in a neg-
ative manner unless temperatures reach very high
levels (over 200 deg. F?) as I'd imagine they are
chosen for temperature resistance, among other
things.

dennis
in nca