Honda EU6500is Owner's Manual page 63

Service according to the table below:
STORAGE TIME
Less than 1 month
1 to 2 months
2 months to 1 year
1 year or more
Use gasoline stabilizers that are formulated to extend storage life.
Follow the manufacturer's instructions for use.
Contact your authorized Honda generator dealer for stabilizer
recommendations.
RECOMMENDED SERVICE PROCEDURE TO
PREVENT HARD STARTING
No preparation required
Fill with fresh gasoline and add gasoline
stabilizer *.
Fill with fresh gasoline and add gasoline
stabilizer *.
Drain the carburetor float bowl (page 62 ).
Drain the fuel sediment cup (page 51 ).
Fill with fresh gasoline and add gasoline
stabilizer *.
Drain the carburetor float bowl (page 62 ).
Drain the fuel sediment cup (page 51 ).
Remove the spark plug. Put a teaspoon of
engine oil into the cylinder. Turn the engine
slowly with the pull rope to distribute the oil.
Reinstall the spark plug.
Change the engine oil (page 47 ).
After removal from storage, drain the stored
gasoline into a suitable container, and fill with
fresh gasoline before starting.
STORAGE
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