Jonsered CS 2166 Workshop Manual page 27

Function
The carburettor operates differently in the following
operating states:
• Cold start
• Idling
• Part throttle
• Full throttle
In cold start mode (fig. 4), the choke butterfly (D) is
completely closed. This increase the vacuum in the
carburettor so that fuel is sucked more easily from the
diffuser jets (E, F and G). The throttle butterfly (H) is
partially open.
In idling mode (fig. 5) the throttle butterfly (H) is closed.
Air is sucked through an aperture in the butterfly and a
small amount of fuel is supplied through the diffuser jet (G).
In part throttle mode (fig. 6) the throttle butterfly (H) is
partially open. Fuel is supplied through the diffuser jets
(F and G).
In full throttle mode (fig. 7) both butterflies are open and
fuel is supplied through all three diffuser jets (E, F and G).
CARBURETTOR
Fig. 4
Fig. 5
Fig. 6
Fig. 7
D E F G
H G
H F
E F
G
G
English – 27