The engine driven fuel pump (bolted to a hot air cooled engine) with a gascolator mounted down where the hottest air exits and near red hot exhaust pipes (standard aircraft practice) is the dumbest fuel system layout I can think of.  And they wonder why they are so prone to vapor lock........
 
Two electrics sound like a fine idea to me.
 
Tracy

    ----- Original Message -----
    From: Jim Sower <mailto:canarder@frontiernet.net>
    To: Rotary motors in aircraft <mailto:flyrotary@lancaironline.net>
    Sent: Wednesday, November 17, 2004 12:13 PM
    Subject: [FlyRotary] External Fuel Pump ...

    All,
    I'm back.  Been away too long.  Lots of catching up to do.

    The problem:
    My  )&$^^$#  Lyc IO-360 went south again.  Blew a head.  Fixed it for
    something over $2k.  Still have a power loss (down to about 60%)
    about
    5-7 min into every flight.  After extensive trouble shooting
    (checking
    everything but fuel pressure which I don't have /yet/) I'm pretty
    sure
    it's fuel [delivery] related.  My 26 psi electric boost pump costs
    $600
    at Spruce.  The Engine driven pump is $225.  I believe they're
    both bad.

    I need:
    An automotive replacement for the electric boost pump.  John Slade
    said
    IIRC that his pumps set him back about $85 each.  I would need to
    plumb
    a return to the sump tank (or back into the inlet) side of the pump)
    through a pressure regulator that I could set at 25-27 psi.

    Does anyone know of a fuel injection rail regulator (or anything
    at all
    that can be plumbed into an AN-6 system) that can be adjusted down to
    regulate at 26 psi?

    Do automotive high pressure fuel pumps allow fuel to pass freely
    if they
    are turned off?  Like, could one plumb two of them in series and use
    them one at a time (as that's what would have to be the case if I
    were
    to retain the engine driven pump)?  If so, what might be the pressure
    drop across the idle boost pump when the engine driven pump is
    carrying
    the load and the boost pump is off?

    What are anyone's thoughts around dispensing with the engine
    driven pump
    and using two electric pumps in parallel?  This idea just popped
    into my
    head as I was writing this, so it's still in the "brain fart" stage.

    Thanks in advance for any and all ideas ... Jim S.

    >>  Homepage:  http://www.flyrotary.com/
    >>  Archive:   http://lancaironline.net/lists/flyrotary/List.html