Honda GXV530 Owner's Manual page 15

Carburetor Modifications for High Altitude Operation
At high altitude, the standard carburetor air*fuet mixture will be
too rich° Performance will decrease, and fuel consumption will
increase. Avery rich mixture will also foul the spark plug and
cause hard starting. Operation at an attitude that differs from that
at which this engine was certified, for extended periods of time,
may increase emissions.
High altitude performance can be improved by specific
modifications to the carburetor. If you always operate your engine
at altitudes above 1,500 meters (5,000 feet), have your servicing
dealer perform this carburetor modification. This engine, when
operated at high altitude with the carburetor modifications for
high altitude use, will meet each emission standard throughout its
useful tifeo
Even with carburetor modification, engine horsepower wilt
decrease about 3°5% for each 300-meter (1,000-foot) increase in
akitudeo The effect of altitude on horsepower will be greater than
this if no carburetor modification is made°
[ NOT!CE ]
When the carburetor has been modified for high altitude operation,
the air-fuel mixture will be too lean for tow 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..
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 appropriate air/fuel ratios and other emissions
control systems to reduce the emissions of carbon monoxide,
oxides of nitrogen, and hydrocarbons,
Additionally, Honda fuel systems utilize components and control
technologies to reduce evaporative emissions°
The U.S,, California Clean Air Acts and Environment Canada
EPA, California 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:
o 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
pa ra meters.
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 idleo
• Misfiring or backfiring under load,
• Afterburning (backfiring),
• Black exhaust smoke or high fuel consumption.
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