Pilots Operating Handbook
63/76
YL-MFG
Revision 7, Issue 1
4/6/2016
7.17.1 Fuel Indication
Fuel quantity is measured by two fuel level sensors located in each fuel tank. Fuel level indicators
and fuel calculator is integrated in Dynon Skyview
CAUTION:
Never fully rely on fuel indicators for fuel levels. It is good practice to know the
approximate amount of fuel added to and/or in the tanks, and to confirm the indicators are
showing correctly.
7.17.2 Fuel Venting
Fuel system venting is essential to system operation. Complete blockage of the fuel venting system
will result in decreasing fuel flow and eventual engine stoppage. The fuel venting system consists
of an interconnecting vent line between the fuel tanks and a check valve equipped overboard vent
in the left fuel tank assembly. The overboard vent protrudes from the bottom surface of the left
wing, just inboard of the wing strut upper attachment point. The fuel filler caps are vacuum vented;
the fuel filler cap vents will open and allow air to enter the fuel tanks in case the overboard vents
become blocked.
7.17.3 Fuel Drain Valves
The fuel system is equipped with 2 drain valves (in the
fuel tanks under each wing) to provide a means for the
examination of fuel in the system for contamination and
grade. The system should be examined before each
flight and after each refueling, by using a sampler cup to
drain fuel from each wing tank sump. If any evidence of
fuel contamination is found, it must be eliminated in
accordance with the preflight inspection checklist and
the discussion in Section 8. If takeoff weight limitations
for the next flight permit, the fuel tanks should be filled
full after each flight to prevent condensation.
7.17.4 Fuel Tank Flushing
To flush the fuel tanks, place the airplane on level ground and remove the aluminum screw with
safety wire in the center of fuselage belly. Turn on the fuel pumps to flush the fuel through the
opening. Once the fuel pumps flush most of the fuel and the stream starts to spit, turn off the
pumps and use the fuel drain valves to drain the rest from each tank. When replacing the aluminum
screw, use a safety wire to fix it from unscrewing.
NOTE
: When flushing from full tanks, since it will take a few minutes with both pumps running,
connect the battery to a charger, to make sure it will not drain during tank flushing.
