Honda G100K2 Applications Manual page 60

ROTATING SCREEN GRID
The engine may overheat due to a drop in cooling efficiency caused by:
•
clogging of the cooling air inlet of the recoil starter housing by straw,
grass clipping (lawn and grass cutting) and other debris.
•
Dirt, dust and mud adhering to the cylinder cooling fins.
The rotating screen grid should be used when operating the equipment in the
presence of excessive amount of straw, grass and debris.
The rotating screen grid restricts the cooling-air flow; the engine operating
temperature may rise and should be watched carefully.
If the screen grid is applied on an engine in semi or full enclosure, the cooling
air intake duct surface should be increased in the same proportion as the
screen grid opening area reduction.
SEMI AND FULL ENCLOSURE – COOLING REQUIREMENTS
An air-cooled engine must transfer the developed heat directly
to the air surrounding the engine. The amount of heat can vary
considerably with the engine power output, but is proportional
as illustrated in the diagram.
If the engine is mounted in an open installation, there should
not be a cooling problem.
If the engine is mounted in a semi or full enclosure, then it is
important to provide:
•
Adequate hot air discharge openings
•
Adequate inward flow of cooling air
•
Supply of cool intake air for aircleaner
•
Adequate ventilation openings to discharge heat when
engine is stopped.
•
Exhaust tube extension
Top louvered opening
Hot air discharge
opening
Full enclosure
Exhaust
system
heat
30%
Muffler extension
Cooling air intake duct
Screen
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TEMPERATURE
Screen grid
Mechanical
energy output
30%
Fuel energy Cooling
input 100%
air heat
30%
Radiation
heat 10%