Honda FR800 Owner's Manual page 46

For storage of a month or longer, perform these additional steps:
3. Fill the fuel tank with fresh gasoline, and add a gasoline conditioner,
such as HONDA FUEL STABILIZER, which is formulated to extend
fuel storage life.
Be sure the fuel tank is completely filled. If partially filled, air in the
tank will promote fuel oxidation and deterioration, resulting in bad fuel
that may cause hard starting. Deteriorated fuel may also clog carbure-
tor passages, requiring carburetor repair or replacement.
Fuel oxidation problems can also be prevented by completely draining
the fuel tank and carburetor. Carburetor draining is recommended if
storage time will exceed two months. However, a drained fuel tank
may rust from the effects of moisture condensation. It is best to leave
the fuel tank completely filled, unless you are preparing the tiller for
shipment or other special circumstances.
NOTE:
The Distributor's Limited Warranty does not cover fuel system
damage of engine performance problems resulting from neglected
storage preparation.
If storage time will not exceed two months, it is not necessary to drain
the carburetor. Add gasoline conditioner before starting the engine
(page 44, step 3 ) ; that will ensure that treated gasoline replaces the
untreated gasoline in the carburetor.
For storage of two months or longer, perform these additional steps:
When transporting or storing the tiller, turn the fuel valve OFF and
keep the tiller level to prevent fuel spillage. Fuel vapor or spilled fuel
may ignite.
Before storing the unit for an
extended period;
4. Be sure the storage area is free of
excessive humidity and dust.
Drain the fuel...
a. With the fuel valve turned OFF,
remove and empty the sediment
cup.
b.Turn the fuel valve ON and drain
the gasoline in the fuel tank into a
suitable container.
44
DRAIN KNOB