Secondary Main System; Acceleration Pump System - Suzuki Samurai 1986 Service Manual

[Secondary main system]

Operation of the secondary throttle valve is also
controlled by the VTV and VSV. When the VSV
is closed, the vacuum to be applied to the
secondary diaphragm passes the VTV side and
the secondary throttle valve opens gradually.
When the primary throttle valve opens almost
fully, the VSV opens according to the signal
from the ECM. Then the vacuum is applied
directly to the secondary diaphragm and the
secondary throttle valve responds to intensity of
vacuum. When the secondary throttle valve open-
ing is wider than when secondary slow system
operates, the fuel is discharged through the
secondary main jet and mixed with the air from
the secondary main air bleeder. The air/fuel
mixture is discharged into the carburetor bore
through the main discharge hole.
Fig. 4-l-9 Secondary main system
1. Secondary main jet
2. Secondary main air bleeder
3. Main discharge hole
4. Primary throttle valve
5. Secondary throttle valve
6. Secondary diaphragm
7. VTV
8. VSV

Acceleration Pump System

This system operates to supply extra fuel to the
primary side only during the acceleration.
When the primary throttle valve closes, the
return spring pushes up the pump piston. Then
the fuel pushes up the check ball and enters into
the pump cylinder. When the throttle valve opens
during the acceleration, simultaneously the
pump piston is pushed down by means of the
pump lever. Then the fuel in the pump cylinder
pushes up the discharge ball and the lower
injector weight and discharges into the carbure-
tor bore from the pump discharge nozzle.
In this way, a higher acceleration performance is
provided by this system.
Fig. 4- l- 10 Acceleration pump s ys tern
2. Return spring
3. Pump piston
4. Check ball
6. Pump cylinder
6. Plunger
7. Pump lever
8. Discharge ball
9. Injector weight
10. Pump discharge nozzle
11. Pump damper spring
4-9