Carburetor Idle Adjustment Points
NOTE: The final idle speed and mixture adjustments are made when the engine is at operating temperature.
Operate the engine until a normal operating temperature is obtained. Make sure the choke plate is fully open. Turn
the idle speed adjustment screw until the desired rpm is obtained. Turn the idle fuel adjustment screw inward until the
engine rpm begins to drop from the lean mixture. Turn the needle outward (counterclockwise) until the engine rpm
increases and just begins to drop from the rich mixture; then turn the screw inward for maximum engine rpm and
smoothness. Always favor a rich mixture rather than a lean mixture for final adjustment. A lean mixture will put an
unnecessary heat load on the valves, and may cause premature valve failure.
Check the engine idle speed and adjust it to specifications if necessary. Final engine idle speed may be varied
within the specified rpm range to suit the conditions under which the unit is to be operated.