FUEL SYSTEM/CARBURETION
4.6
CARBURETOR OPERATION CONT’D
When the throttle plate is opened and engine speed
begins to increase, the pressure in the venturi (and
therefore in the chamber above the diaphragm)
becomes significantly lower than atmospheric.
Atmospheric pressure in the chamber below the
diaphragm forces the diaphragm upward, raising the
slide against spring pressure. When the pressure
above and below the diaphragm are nearly equal, the
slide moves downward under spring pressure.
Raising or lowering the slide increases or decreases
the cross sectional area in the venturi, and therefore
the air velocity in the venturi is kept relatively constant.
This provides improved fuel atomization and optimum
fuel/air ratio.
= Air Flow
= Low Pressure
Low Pressure
From Venturi
From
Air Box
Throttle
Plate
Diaphragm
Vacuum
Slide
Venturi
Note: Diagrams are for explanation of theory only, and are not true
representations of Mikuni BST carburetor.
PILOT (IDLE AND SLOW)
SYSTEM
This system supplies fuel during engine operation
with throttle valve closed (1) or slightly opened. The
fuel from float chamber (2) is metered by pilot jet (3)
where it mixes with air coming in through pilot air jet
(4). The mixture then goes up through pilot passage
to pilot screw (5). A part of the mixture is discharged
into the main bore out of bypass ports (6). The
remainder is then metered by pilot screw and
discharged into the main bore through pilot outlet (7).
4
1
6
7
5
2
3
STARTER SYSTEM (CHOKE
OR ENRICHMENT)
When the choke cable (1) is activated, the starter
plunger (5) is lifted off the seat.
1
5
8
6
4
2
3
7
Fuel is drawn into the starter circuit from the float
chamber (2) through the starter jet (3). Starter jet
meters this fuel, which then flows into starter pipe (4)
and mixes with the air (7) coming from the float
chamber. The mixture, rich in fuel content, reaches
starter plunger and mixes again with the air coming
through a passage (8) extending from underneath the
diaphragm. The rich fuel/air mixture for starting is
discharged through starter outlet (6) in the the main
bore.
Содержание 600 Dragon SP
Страница 1: ...2004 SPORTSMAN 600 700 SERVICE MANUAL PN 9918803 ...
Страница 138: ...BODY STEERING SUSPENSION 5 16 NOTES ...
Страница 210: ...FINAL DRIVE 7 38 NOTES ...
Страница 293: ...ELECTRICAL 10 43 WIRING DIAGRAM HAND AND THUMB WARMERS WINCH HUNTER EDITION ...
Страница 294: ...ELECTRICAL 10 44 NOTES ...
Страница 295: ...ELECTRICAL WIRING DIAGRAM EARLY 2004 SPORTSMAN 600 700 BUILT BEFORE FEB 20 2003 Built Before February 20 2003 ...
Страница 297: ...ELECTRICAL WIRING DIAGRAM LATE 2004 SPORTSMAN 600 700 BUILT AFTER FEB 20 2003 Built After February 20 2003 ...
Страница 298: ...ELECTRICAL WIRING DIAGRAM LATE 2004 SPORTSMAN 600 700 BUILT AFTER FEB 20 2003 Built After February 20 2003 NOTES ...
Страница 299: ...ELECTRICAL WIRING DIAGRAM LATE 2004 SPORTSMAN 600 700 MODELS WITH FUEL GAUGE Models Equipped with Fuel Gauge ...
Страница 300: ...ELECTRICAL WIRING DIAGRAM LATE 2004 SPORTSMAN 600 700 MODELS WITH FUEL GAUGE NOTES ...
Страница 301: ...ELECTRICAL WIRING DIAGRAM 2004 SPORTSMAN 600 700 HUNTER EDT HAND WARM WINCH ...
Страница 307: ...Winch Switch Installation 10 34 Winch Wiring 10 35 Wiring Diagram Hand Thumb Warmer Winch 10 43 ...
Страница 308: ...PN 9918803 Printed in USA ...