Oxygenated Fuels; Emission Control System Information - Honda GX120 Manual Del Propietário

Even with carburetor modification, engine horsepow er will
decrease about 3.5% for each 300-m eter (1,000-foot) increase in
altitude. The effect of altitude on horsepow er w ill be greater than
this if no carburetor m odification is m ade.
When the carburetor has been modified for high altitude operation,
the air-fuel mixture will be too lean for low altitude use. Operation
at altitudes below 1,500 meters (5,000 feet) with a modified
carburetor may cause the engine to overheat and result in serious
engine damage. For use at low altitudes, have your servicing
dealer return the carburetor to original factory specifications.

Oxygenated Fuels

Som e conventional gasolines are being blended w ith alcohol or an
ether com pound. These gasolines are collectively referred to as
oxygenated fuels. To m eet clean air standards, som e areas of the
United States and Canada use oxygenated fuels to help reduce
em issions.
If you use oxygenated fuel, be sure it is unleaded and m eets the
m inim um octane rating requirem ents.
Before using an oxygenated fuel, try to confirm the fuel's contents.
Som e states/provinces require this inform ation to be posted on
the pum p.
The following are the EPA approved percentages of oxygenates:
(ethyl or grain alcohol) 10% by volum e
ETHANOL
You m ay use gasoline containing up to 10%
ethanol by volum e. Gasoline containing
ethanol m ay be m arketed under the nam e
Gasohol.
(m ethyl tertiary butyl ether) 15% by volum e
MTBE
You m ay use gasoline containing up to 15%
MTBE by volum e.
(m ethyl or w ood alcohol) 5% by volum e
METHANOL
You m ay use gasoline containing up to 5%
m ethanol by volum e as long as it also
contains cosolvents and corrosion inhibitors
to protect the fuel system . Gasoline
containing m ore than 5% m ethanol by
volum e m ay cause starting and/or
perform ance problem s. It m ay also dam age
m etal, rubber, and plastic parts of your fuel
system .
If you notice any undesirable operating sym ptom s, try another
service station or sw itch to another brand of gasoline.
Fuel system dam age or perform ance problem s resulting from the
use of an oxygenated fuel containing m ore than the percentages
of oxygenates mentioned above are not covered under the
Distributor's Limited Warranty .

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 im portant because, under certain conditions,
they react to form photochemical smog w hen subjected to
sunlight. Carbon monoxide does not react in the same w ay, but it
is toxic.
Honda utilizes lean carburetor settings and other system s to
reduce the em issions of carbon monoxide, oxides of nitrogen, and
hydrocarbons.
The U.S., California Clean Air Acts and Environment Canada
EPA, California and Canadian regulations require all
manufacturers to furnish w ritten instructions describing the
operation and m aintenance of em ission control systems.
The following instructions and procedures must be follow ed in
order to keep the em issions from your Honda engine w ithin the
em ission standards.
Tampering and Altering
Tam pering w ith or altering the em ission control system m ay
increase em issions beyond the legal lim it. Am ong those acts that
constitute tam pering are:
Rem oval or alteration of any part of the intake, fuel, or exhaust
system s.
Altering or defeating the governor linkage or speed-adjusting
mechanism to cause the engine to operate outside its design
param eters.
Problems That May Affect Emissions
If you are aw are of any of the follow ing sym ptom s, 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 sm oke or high fuel consumption.
Replacement Parts
The em ission control systems on your Honda engine w ere
designed, built, and certified to conform w ith EPA, California and
Canadian em ission regulations. We recommend the use of
genuine Honda parts w henever you have m aintenance done.
These original-design replacement parts are manufactured to the
same standards as the original parts, so you can be confident of
their perform ance. The use of replacement parts that are not of the
original design and quality m ay im pair the effectiveness of your
em ission control system.
A m anufacturer of an aftermarket part assumes the responsibility
that the part w ill not adversely affect em ission performance. The
manufacturer or rebuilder of the part m ust certify that use of the
part will not result in a failure of the engine to comply w ith
em ission regulations.
Maintenance
Follow the maintenance schedule on page . Remember that this
schedule is based on the assumption that your machine w ill be
used for its designed purpose. Sustained high-load or high-
tem perature operation, or use in unusually w et or dusty conditions,
will require m ore frequent service.
ENGLISH
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