Husqvarna TrioBrake 550XPG - Page 40

40 - English
Repair Instructions
Function
The carburettor operates dierently in the following
modes:
• Cold start mode
• Idling mode
• Part throttle mode
• Full throttle mode
In cold start mode the choke valve H is completely
shut. This increases the vacuum in the carburettor
and fuel is easier to suck from all the diuser jets
D, E, and F. The throttle valve I is partly open. The
air throttle valve, J, is closed. See gure 30.
Fig 30
In idling mode, the throttle valves I and J are
closed and the choke valve H is open.
Air is sucked in through an aperture in the throttle
valve and a small amount of fuel is supplied
through the diuser jet D. See gure 31.
Fig 31
In part throttle mode, the throttle valve I is partly
open and the choke valve H is fully open. Fuel is
supplied through the diuser jets D and E. The air
throttle valve, J, starts to open. See gure 32.
Fig 32
In the full throttle mode both valves are open and
fuel is supplied through all four diuser jets (D, E,
F and G). The air throttle valve, J, is fully open. See
gure 33.
Fig 33