Honda EB4000 Owner's Manual page 10

2. Check the fuel level.
Use automotive gasoline with a research octane of 91 or higher or a pump
octane of 86 or higher.
Never use an oil/gasoline mixture or dirty gasoline. Avoid getting dirt, dust
or water in the fuel tank.
CAUTION: Gasoline substitutes are not recommended; they may be
harmful to the fuel system components.
Gasoline is extremely flammable and explosive under certain conditions.
Refuel in a well ventilated area with the engine stopped.
Do not smoke or allow flames or sparks in the area where the generator
is refueled or where gasoline is stored.
Do not overfill the tank and make sure the filler cap is securely closed
after refueling.
Be careful not to spill fuel when refueling. Fuel vapor or spilled fuel may
ignite. If any fuel is spilled, make sure the area is dry before starting the
engine.
FUEL TANK CAP
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