Coupers,

In a recent posting someone wrote:  

<<We all know the fuel pump is an automotive pump.>>

I'd like to share some info concerning Aircoupe fuel pumps that some might
find interesting.

Many years ago when I needed a fuel pump for my 1966 Alon, I ordered one
from
an aviation parts supplier who said that it was the right one for my
engine.
The part number of this pump didn't match the part number on the old one,
and
to make a long story shorter, I ended up talking directly to an enginner
who
worked for AC's fuel pump division.  He explained to me that the
difference
between the different part numbers on the fuel pumps was in the geometry
of
the actuating lever on the pump.  Evidently different versions of the C-90
engines had different height lobes on the crankshaft to actuate the fuel
pump.
He told me that putting the wrong fuel pump on the engine could cause the
fuel
pump lever to be overstressed resulting in the lever breaking and falling
into
the crankcase, or in the opposite instance, could cause the fuel pump to
not
pump enough fuel due to the actuator not being stroked the proper
distance.

Since that time I have heard of at least one instance where someone had a
fuel
pump lever fail.  I always wondered if that might have been caused by
having
the wrong part number fuel pump installed.

My point in sharing this story is that sometimes it's pretty difficult for
an
individual to determine if a nonstandard part is really safe in all
respects.
My original fuel pump and the new one with the wrong part number looked
exactly the same to me until that engineer told me what the difference
was. 

Fly Safe,

Wayne DelRossi
Alon N5618F

<<attachment: winmail.dat>>

Reply via email to