Carburetor Modifications For High Altitude Operation; Emission Control System - Honda GX120 Owner's Manual

05/02/09 13:19:57 32Z4F800_012
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 oxygenated fuel, be sure it is unleaded and meets the
minimum octane rating requirements.
Before using an oxygenated fuel, try to confirm the fuel's contents.
Some states/provinces require this information to be posted on
the pump.
The following are the EPA approved percentages of oxygenates:
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.
MTBE (methyl tertiary butyl ether) 15% by volume
You may use gasoline containing up to 15%
MTBE by volume.
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 the
Distributor's Limited Warranty .
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Emission Control System Information
Source of Emissions
The combustion process produces carbon monoxide, oxides of
nitrogen, and hydrocarbons. Control of hydrocarbons and oxides
of nitrogen is very important because, under certain conditions,
they react to form photochemical smog when subjected to
sunlight. Carbon monoxide does not react in the same way, but it
is toxic.
Honda utilizes lean carburetor settings and other systems to
reduce the emissions of carbon monoxide, oxides of nitrogen, and
hydrocarbons.
The U.S. Clean Air Acts and Environment Canada
EPA and Canadian regulations require all manufacturers to furnish
written instructions describing the operation and maintenance of
emission control systems.
The following instructions and procedures must be followed in
order to keep the emissions from your Honda engine within the
emission standards.
Tampering and Altering
Tampering with or altering the emission control system may
increase emissions beyond the legal limit. Among those acts that
constitute tampering are:
Removal or alteration of any part of the intake, fuel, or exhaust
systems.
Altering or defeating the governor linkage or speed-adjusting
mechanism to cause the engine to operate outside its design
parameters.
Problems That May Affect Emissions
If you are aware of any of the following symptoms, have your
engine inspected and repaired by your servicing dealer.
Hard starting or stalling after starting.
Rough idle.
Misfiring or backfiring under load.
Afterburning (backfiring).
Black exhaust smoke or high fuel consumption.
Replacement Parts
The emission control systems on your Honda engine were
designed, built, and certified to conform with EPA and Canadian
emission regulations. We recommend the use of genuine Honda
parts whenever you have maintenance done. These original-
design replacement parts are manufactured to the same standards
as the original parts, so you can be confident of their performance.
The use of replacement parts that are not of the original design
and quality may impair the effectiveness of your emission control
system.
A manufacturer of an aftermarket part assumes the responsibility
that the part will not adversely affect emission performance. The
manufacturer or rebuilder of the part must certify that use of the
part will not result in a failure of the engine to comply with
emission regulations.
Maintenance
Follow the maintenance schedule on page . Remember that this
schedule is based on the assumption that your machine will be
used for its designed purpose. Sustained high-load or high-
temperature operation, or use in unusually wet or dusty conditions,
will require more frequent service.
ENGLISH
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