Mixture Control Valve Adjustment; Realignment Of Mixture Control Valve - O.S. engine MAX FXi 46 Owner's Instruction Manual

MIXTURE CONTROL VALVE
ADJUSTMENT
With the engine running, close the throttle
and allow it to idle for about five seconds,
and then open the throttle fully. If, at this
point, the engine is slow to pick up and
produces an excess of exhaust smoke, the
mixture is too rich. Correct this condition by
turning the Mixture Control Screw clockwise
15-30°. If the mixture is excessively rich,
engine RPM will become unstable: opening
the throttle will produce a great deal of
smoke and RPM may drop suddenly or the
engine may stop. This condition may also
be initiated by excessively prolonged idling.
If, on the other hand, the mixture is too lean,
this will be indicated by a marked lack of
exhaust smoke and a tendency for the
engine to cut out when the throttle is
opened. In this case, turn the Mixture
Control Screw counterclockwise 90° to
positively enrich the idle mixture, then turn
the screw clockwise gradually until the
engine regains full power cleanly when the
throttle is reopened.
Carry out adjustments patiently until the
engine responds quickly and positively to
the throttle control.
Note: Mixture Control Valve adjustments
should be made in steps of 15-30° initially,
carefully checking the effect, on throttle
response, of each small adjustment.
REALIGNMENT OF MIXTURE
CONTROL VALVE
In the course of making carburetor
adjustments, it is just possible that the
Mixture Control Valve may be inadvertently
screwed in or out too far and thereby moved
beyond its effective adjustment range. Its
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