Fuel pump questions

[Shannen Durphey]

Clare Snyder wrote:

> sfg wrote:
> >
> > Frederic Breitwieser wrote:
> > >
> > > > As for sparking: I have the same question.
> > > > That's a brush-type motor in the tank! What if
> > > > fuel level is at min, and the motor brushes are exposed?
> > > > Steve
> >
> > ...snip
> > > The in-tank fuel pumps are sealed
> > > as to prevent the armature from being saturated with gasoline...
> > ...snip
> >
> > I took my failed GM OEM pump to bits to see what broke. It APPEARED
> > to me like the fuel had free access to the armature and brushes.
> > I saw nothing in there to prevent gas from getting in. BTW, failure
> > was due to 1 of the 2 plastic rotors being split. Brushes were 50%
> > worn down after 120,000 miles. The Mexican pump I replaced
> > it with (AutoZone) lasted 2 months. So I now run the Mallory
> > 4060FI external in-line (having lost the desire to drop the
> > tank again)    Steve
>
> You are correct - the armature is directly cooled by immersion in
> gasoline. One reason to never run a FI'd engine too low on fuel - the
> pump will overheat. On a FI'd vehicle that has sat with the gas cap off
> for a good lenth of time, ALWAYS top up the tank before attempting to
> start the engine - to drive out any air drom the tank and render the
> mixture too dense to ignite.
> --
>                              _/\_
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>                        S    0/  \0    B
>
> Remove the R from E-Mail Address to reply. Stop the spammers!!!
> It's hard to soar like an eagle when your stuck with a bunch of
> Turkeys

  And too add a little more, if you are in any position to notice, most GM
fuel pumps fail when the copper contacts on the armature are worn through
and the brushes are at about 50% life. If someone could make a pump with an
AC motor and small inverter, or maybe DC brushless?? then it should last
forever.

Shannen