Operating Instructions & Parts Manual
2 Inch & 3 Inch Water Pump
Carburetor Modification For High Altitude Operation
At high altitude, the standard carburetor air-fuel mixture will be to rich. Performance will decrease, and fuel
consumption will increase. A very rich mixture will also foul the spark plug and cause hard starting. Operation at
an altitude 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 5000 feet (1500 meters), have a qualified mechanic perform this carburetor modifica-
tion. This engine, when operated at high altitude with the carburetor modifications for high altitude use, will
meet each emissions standard throughout its useful life.
Even with the carburetor modifications, engine horsepower will decrease about 3.5% for each 1000 foot (300
meter) increase in altitude. The effect of altitude on horsepower will be greater than this if no carburetor
modification is made.
Note:
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 5000 feet (1,500 meters)
with a modified carburetor may cause the engine to overheat and result in serious engine damage. For
use at low altitudes, have a qualified mechanic return the carburetor to original factory specifications.
Replacement Parts
The emission control system on your engine were designed, built, and certified to conform with EPA and
California emissions regulations. We recommend the use of original replacement part whenever you have
maintenance done. These original designed 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 you emissions control system.
A manufacturer of an aftermarket part assumes the responsibility that the part will not adversely affect emission
performance. The manufacturer or builder of the part must certify that use of the part will not result in a failure of
the engine to comply with emission regulation.
Note:
Specifications may vary according to the types, and are subject to change without
notice.
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