High Altitude Operation - Honda EB6500 Owner's Manual

3.Turn the fuel valve to the OFF position.
FUEL VALVE
l
High altitude operation
At high altitude, the standard carburetor air-fuel mixture will be
excessively rich. Performance will decrease, and fuel consumption will
increase.
High altitude performance can be improved by installing a smaller diameter
main fuel jet in the carburetor and readjusting the pilot screw. If you always
operate the engine at altitudes higher than 6,000 feet above sea level, have
an authorized Honda generator dealer perform this carburetor modification.
Even with suitable carburetor jetting, engine horsepower will decrease
approximately 3.5% for each 1,000 foot increase in altitude. The effect of
altitude on horsepower will be greater than this if no carburetor modifica-
tion is made.
Operation of the generator at an altitude lower than the carburetor is
jetted for may result in reduced performance, overheating, and serious
engine damage caused by an excessively lean air/fuel mixture.
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