Daewoo G424 Gasoline, Service Manual

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G424 Service Manual Gasoline Fuel System 62
The idle compensator uses a bimetal. When the
carbretor ambient temperature rises during idle or
“off idle” running, the bimetal bends enough to open
the compensator valve. Now additional air from the
choke bore can flow through the auxiliary air
passage to the intake manifold directly. It leans out
the mixture enough to make up for the proper
richness.
4. Main metering system
The wider the throttle valve opens, the faster the air
flow in the venturi and the greater the vacuum in the
inner venturi will be. As the vacuum becomes
greater, additional fuel is discharged from the main
nozzle.
The main metering system is provided with the
bleed valve press-fitted to the inner venturi and the
main air jet.
Fuel metered by the main jet is bled by air from the
main air jet and enters the bleed pipe through its
holes. The fuel is discharged from the main nozzle
and sucked by engine cylinders.
If percolation of fuel arises along the main well,
gasoline vapor can escape from the main air jet
through the relatively wide outside of the bleed
pipe. This prevents liquid fuel from spurting from the
main nozzle, thus assuring stable engine operation
and easy restarting.
To prevent percolation due to conduction of heat
from the engine, sufficient cooling of the float
chamber periphery is taken into consideration in
design of the carburetor.
Idle Compensator Main Metering System