The manual states that the "external tank" pumps
will override the main tank pumps while the
Ext tanks have fuel in them;  however with all
tanks full at departure and all pumps "on",   no fuel
was being drawn from the Ext tanks or Aux tanks.
Fuel was being drawn only from the main tanks.
>>Quote from Manual 2 :
"Both pumps have overriding output pressures which under normal operation ensure depletion of fuel from the external tanks before the main tanks are affected."
>> Also, regarding the Aux tank pumps :
"there is no source of higher pressure to that side of the manifold" > which seems to state that fuel in the
Aux tanks (as well as fuel in the External tanks) will
be used before fuel is drawn from the main tanks.

Any tips or comments will be appreciated.
Ken