Good advice from Harry Francis.  I might add that when the overflow line
from the nose to the left wing tank is open and free flowing, if you put
gas into the nose tank while continuing to fuel the airplane at a slow
rate, you can visually see the fuel level in the left wing tank come up
after the nose tank fills, and the extra fuel you put in it overflows
normally, thru the line, into left wing.
Jusy take the cap off of the left wing tank, fuel as you normally would
thru the nose, but at a slow rate to keep from spilling a mess all over
the cowling.  If the left wing tank doesn't come up after the nose is
full, and you get spillage on the cowling, your line from the nose to left
wing is plugged.
When I want to be sure that our plane is totally full, for a X-country, I
sometimes use this technique.
Jerry Eichenberger
Columbus, Ohio
N2906H

>>> <[EMAIL PROTECTED]> 02/09/99 02:35PM >>>
On a 415 Coupe, the fuel pump  transfers fuel from the right tank to the
cowl
tank, at just slightly more than the engine can use at full throttle. The
excess is drained back to the wing tank.

The fuel pump capacity is much greater than the fuel need, so a restrictor
fitting is placed in the outlet port of the fuel pump, to limit its
output. If
a pump is replaced with out the restrictor, then this is most likely the
problem.

The drain line from the cowl tank can become partially plugged. if it
does,
then the excess fuel pumped ( normal excess - not excess if there is no
restrictor in the pump outlet), cannot drain back to the wing tank - thus
it
overflows out the cowl tank cap vent hole. The cap with float should be
installed with the vent hole to the front. Trace and remove fitting,  and
clean the line.  If the line is plugged, the tank should be cleaned of
foreign
materials, so the outlet to the engine doesn't become clogged.

You can check this line by blowing on the main tank opening, and have a
helper
listening at the wing tank. Do not pressurize with an air hose.....You
should
be able to freely blow into tank, and hear bubbles in the wing tank. Don't
inhale !

NOT A GOOD THING TO HAVE RAW GASOLINE FLOWING DOWN INTO THE COWL, ACROSS
THE
HOT MUFFLER AND SEEPING INTO THE COCKPIT !!!

The wing tank caps should also have vent holes. When installed, the holes
should be toward the front of the airplane, so that relative airstream
slightly pressurizes the tank. 

If the fuel caps are installed with the hole (s) to the rear of the
airplane,
then fuel will be sucked overboard...from the vacumn formed by relative
airstream.

Service Bulletin  #31 describes the proceedure for making the tank
fittings
with flanges so that the cap cannot be installed improperly.

To keep water out of the tanks, Use a baby bottle silicone nipple to slide
over the float wire, to prevent water from draining into the tank. Make
hole
in nipple with hot needle - otherwise you will surely tear it. Remove the
nipple prior to flight...as part of your pre-flight inspection.

Hope this gets the coupe back in the air.

Fly Safe - Have Fun

Harry Francis
N 93530
Blacksburg, Va.

 

 
!
!
 

 
!
!
 

<<attachment: winmail.dat>>

Reply via email to