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LONG-EZ. DEFIANT, ELECTRIC BOOST FUEL PUMP ALERTFrom CP57, Page 11 (October, 1988)
Returning to his home base
airport after a flight, a Southern California Long-EZ pilot was approaching the 45 degree
entry to downwind when, abruptly, his engine quit. He was unsuccessful in getting it
restarted but, to his credit, he flew the airplane, announced his situation and made an
uneventful, successful landing. Feeling a little weak around the knees, he pushed his
airplane into his hangar and went home.
The next day, he conducted a careful examination of the aircraft
and discovered that the Facet solid-state fuel pump was completely blocked and would not
allow any fuel to pass through to the engine driven mechanical pump! One of the two valves
in the pump had deteriorated in the 100LL fuel and had worked its way out of the metal
cage that normally prevents this, and had been sucked into a position that prevented the
flow of fuel. The part number on the mounting flange of this pump was 480615. The plunger
valve was made of VITON- this pump is no longer being manufactured.
Before next flight, check the part number of your pump. If you
have one of the following part numbers 40023, 480615, 480616, remove the pump and replace
The most desirable Facet solid-state pumps that we recommend are
part #40108 for 12 volts and part # 40154 or 480610 for 24 volts. Both pump fuel at a
regulated maximum 6 psi, and the valves in these pumps are pure nyIon which, other than
swelling very slightly in avgas, are not affected nor do they deteriorate. The design of
these valves (the foot valve and the plunger valve) are such that they cannot physically
get into a position where they can prevent fuel from flowing through the boost pump. Both
of the above pumps have AN-style, 370 flare fittings which fit 3/8" tube, AN 818-6.
Facet manufactures over one hundred variations of the small
square solid-state fuel pumps. The above two pumps have AN-type flare fittings machined
right on the pump bodies and we prefer this type because they are easy to install (no
elbows or nipples required), but also because these two models have only nylon
valves, no rubber, Buna, or Viton. Many of FACET's other models have Viton plunger valves
or Buna N check valves and these will deteriorate in avgas. These are specifically
for use in some other liquid known not to affect these materials.
To check your pump, remove it and look into the inlet and the
outlet using a small flashlight and verify that the inlet valve (foot valve) is a round,
white dome or ball (nylon), not a flat, black rubber disc. Verify that in the
outlet there is a white nylon valve under a steel pin which crosses the port and retains
this valve. If this valve is dark gray or black (Viton), remove the pump before next
flight and discard it. If you have to a pump with female pipe threads (to accept elbows or
nipples) due to your firewall layout, choose one with 3/8 NPT female threads rather than
the 1/8NPT female threads, but examine it closely to be sure it has while nylon
valves in the inlet and the outlet ports. Discard it if there is any black or gray Viton,
Buna N or rubber valves.
If you have had your Facet fuel pump more than a year or so, you
probably have one that could go bad. AT a cost of approximately $30.00, it is not worth
the risk. Remove it, discard it and install a new one as called out. We believe
that the serious consequences that could result from a fuel supply stoppage, more than
justifies the immediate replacement of any suspect pump.
We have replaced the boost pumps on Burt's Defiant and on Mike
and Sally's Long-EZ and we recommend in the strongest
possible terms that you do the same.