Honda Marine BF9.9D Owner's Manual page 91

The length of time that gasoline can
be left in your fuel tank and
carburetor without causing functional
problems will vary with such factors
as gasoline blend, your storage
temperatures, and whether the fuel
tank is partially or completely filled.
The air in a partially filled fuel tank
promotes fuel deterioration. Very
warm storage temperatures accelerate
fuel deterioration. Fuel deterioration
problems may occur in less than 30
days, if the gasoline was not fresh
when you filled the fuel tank.
You can extend fuel storage life by
adding a gasoline stabilizer that is
formulated for that purpose, or you
can avoid fuel deterioration problems
by draining all the fuel from the fuel
tank and carburetor.
Adding a Fuel Stabilizer
When adding a fuel stabilizer, fill the
fuel tank with fresh gasoline. If only
partially filled, air in the tank will
promote fuel deterioration during
storage. If you keep an additional
container of gasoline for refueling,
be sure that it contains only fresh
gasoline.
1. Add fuel stabilizer following the
manufacturer's instructions.
2. After adding a fuel stabilizer, run
the engine in water for 10 minutes
to be sure that the treated gasoline
has replaced the untreated gasoline
in the carburetor.
3. Turn the engine OFF.
The Distributor's Limited Warranty
(p. 123 ) does not cover fuel system
damage or engine performance
problems resulting from neglected
storage preparation.
STORAGE
Draining the Fuel System
You can avoid fuel deterioration
problems by draining the fuel tank
and carburetors.
1. Disconnect the fuel hose from the
outboard motor.
DRAIN SCREW
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