BRP 2995 Johnson - Carburetor Operation; Float System; Idlingitrolling

FUEL SYSTEM
CARBURETOR OPERATION
CARBURETOR OPERATION
Float system
Idling/Trolling
1. Pilot jet
2. Pilot air jet
3. Pilot outlet
4. Bypass port
#1
5. Pilot screw
¢=:J AIR
.. FUEL +AIR (MIXTURE)
.. FUEL
, ,
, ,
After passing through the pilot jet, fuel mixes with air supplied from the pilot air jet.
This mixture passes through the
pilot screw seating area and is jetted both from the pilot outlet and
bypass port #1.
No mixture is jetted either from the bypass port #2 or from those located upstream. These ports serve as
air passages.
As the pilot screw is turned clockwise (screwed in), the mixture (AlF)
will become leaner. As the screw is
turned counterclockwise (screwed out), the mixture
will become richer.
The
throttle stop screw adjusts idling/trolling speed. When the stop screw is turned clockwise (screwed
in), the speed raises and when turned counterclockwise (screwed out), the speed
lowers.
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