4-20 FUEL SYSTEM
OPERATION
CARBURETOR
Float system
Idling/Trolling
After passing through the pilot jet 1, fuel mixes with air that is supplied from the pilot air jet 2.
This mixture then passes through the pilot screw 5 seating area and is jetted both from the pilot outlet 3
and bypass port #1 4.
No mixture will be jetted either from the bypass port #2 or from those located upstream but these ports serve
as air passage.
As the pilot screw 5 is turned clockwise (screwed in), the mixture (A/F) will become leaner. As the screw is
turned counterclockwise (screwed out), the mixture will become richer.
The throttle stop screw is designed to adjust the idling/trolling speed. When the stop screw is turned clock-
wise (screwed in), the speed raises and when turned counterclockwise (screwed out), the speed lowers.
Fuel inlet joint
Float valve
Float pin
Float valve seat
Float
FUEL
AIR
FUEL+AIR (MIXTURE)
FUEL
Pilot jet
Pilot air jet
!
Pilot outlet
"
Bypass port #1
#
Pilot screw
To Next Page
Loading...
