Honda HRC7018 Owner's Manual page 48

MAINTENANCE & ADJUSTMENTS
Running the engine with persistent spark knock or pinging
can cause engine damage. This type of damage is not
covered by the Distributor's Limited Warranty.
Oxygenated Fuels
Some conventional gasolines are being blended with alcohol
or an ether compound. These gasolines are collectively
referred to as oxygenated fuels. To meet clean air standards,,
some areas of the United States and Canada use
oxygenated fuels to help reduce emissions. If you use an
oxygenated fuel, be sure it is unleaded and meets the
minimum octane rating requirement.
Before using an oxygenated fuel, try to confirm the fuel's
contents. Some states and provinces require this information
to be posted on the pump. The following are the EPA
approved percentages of oxygenates:
l
Ethanol (ethyl or grain alcohol) 10% by volume
You may use gasoline containing up to 10% ethanol by
volume. Gasoline containing ethanol may be marketed under
the name "Gasohol".
l
MTBE (methyl tertiary butyl ether ) 15% by volume
You may use gasoline containing up to 15% MTBE by
volume.
l
Methanol (methyl or wood alcohol) 5% by volume
You may use gasoline containing up to 5% methanol by
volume as long as it also contains cosolvents and corrosion
inhibitors to protect the fuel system. Gasoline containing
more than 5% methanol by volume may cause starting
and/or performance problems. It may also damage metal,
rubber, and plastic parts of your fuel system. If you notice
any undesirable operating symptoms, try another service
station or switch to another brand of gasoline.
Fuel system damage or performance problems resulting from
the use of an oxygenated fuel containing more than the
percentages of oxygenates mentioned above are not
covered under warranty.
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