Cessna Grand Caravan 208B G1000 Manual page 506

SECTION 8 CESSNA
HANDLING, SERVICE, AND MAINTENANCE MODEL 208B G1000
FUEL CONTAMINATION
Fuel contamination is usually the result of foreign material present in
the fuel system and may consist of water, rust, sand, dirt, microbes, or
bacterial growth. In addition, additives that are not compatible with fuel
or fuel system components can cause the fuel to become
contaminated.
Before each flight and after each refueling, use a clear sampler and
drain at least one sampler full of fuel from the inboard fuel tank sump
quick-drain valves, fuel tank external sump quick-drain valves, fuel
reservoir quick-drain valve (actuated by a push-pull drain control on
cargo pod), and fuel filter quick-drain valve to determine if contaminants
are present and that the airplane has been fueled with the proper fuel. If
the airplane is parked with one wing low on a sloping ramp, draining of
the outboard fuel tank sump quick-drain valves (if installed) is also
recommended.
If contamination is detected, drain all fuel drain points again. Take
repeated samples from all fuel drain points until all contamination has
been removed. If (after repeated sampling) evidence of contamination
still exists, the fuel tanks should be completely drained and the fuel
system cleaned.
Do not fly the airplane with contaminated or unapproved fuel. Anytime
the filter bypass flag (red warning button) is found to be extended, the
filter element has become clogged. Disassemble the filter, clean the
element, and check the fuel system to determine the cause of
contamination before further flight.
In addition, owners/operators who are not acquainted with a particular
fixed base operator must verify that the fuel supply has been checked
for contamination and is properly filtered before allowing the airplane to
be serviced. Also, fuel tanks must be kept full between flights, provided
weight and balance considerations will permit, to reduce the possibility
of water condensing on the inside walls of partially filled tanks.
(Continued Next Page)
208BPHBUS-00
U.S.
8-22