1. Put a hose on the air purge bulb connection of the
carburetor
2. Blow in and out.
The valve must close when you blow in to the carburetor
and open when you blow out.
6.6.12 Function measurement chamber
The product has SmartCarb
™
filter compensation. The
measurement chamber has 2 chambers. The air
chamber to the cover and a fuel chamber to the
carburetor body. These are divided by the measurement
chamber diaphragm. The diaphragm controls and keeps
a constant level of fuel in the fuel chamber through the
mechanically connected needle valve. The air chamber
is near the inlet, after the air filters, and gives the air
chamber the same pressure.
6.6.13 To examine the measurement chamber
diaphragm
Assemble the parts in the order shown in the figure. The
gaskets (1) are the same.
1
1
1. Examine the diaphragm visually. Fuel on the top
side, to the cover, is a sign of leaks. If there is fuel
on the top side, replace the diaphragm.
6.6.14 Function pump unit
The pump diaphragm (1) gets power by changes of
pressure in the crankcase. They are caused by the
movement of the piston. They are transmitted to the top
of the pump diaphragm. The fuel below the diaphragm is
pushed to the valves (2). Pressure from the
measurement chamber diaphragm to the needle valve in
the measurement chamber controls how much the valve
42 - Repair and servicing
701 - 002 -