To Adjust Carburetor; Initial Adjustment; Final Adjustment - Craftsman 2One 917.372471 Owner's Manual

ENGlNE
TO ADJUST CARBURETOR (See Fig. 18 )
Minor carburetor adjustments may be required to com-
pensate for differences in fuel, temperature, altitude or
toa.d. The air cleaner and air cleaner cover must be
assembled to carburetor when running.
INITIAL ADJUSTMENT-
With the engine not running, gently turn idle mixture screw
clockwise until it just closes. Screw may be damaged by
turning it in too far.
Next open the screw one turn counter-clockwise. This
initial adjustment will permit the engine to be started and
warmed up (approximately 5 minutes) prior to final ad-
justment.
NOTE: DO NOT adjust top no load adjusting screw. It was
pre-set at the factory,
FINAL ADJUSTMENT-
Place engine speed control lever in "IDLE" or "SLOW"
(,g_) position. Adjust idle RPM by turning idle speed
adjusting screw to obtain 1400 RPM. Next, turn idle mixture
screw in (clockwise- lean mixture) until engine just starts to
slow. Then turn idle mixture screw out (counter-clockwise
- rich mixture) until engine runs unevenly. Now turn idle
mi_ure screw midway between rich and lean. Engine
should accelerate smoothly. If engine does not accelerate
properly, the carburetor should be readjusted, usually to a
richer mixture, by turning the idle mixture screw counter-
clockwise 1/8 turn more.
TOP NO
LOAD
SCREW
IDLE SPEED
ADJUSTING
SCREW
IDLE
MIXTURE
FIG. 18
ENGINE SPEED
Your engine speed has been factory set. Do not attempt
to increase engine speed or it may result in personal
injury. If you believe that the engine is running too fast or
too slow, take your lawn mower to an authorized Sears
Service Center for repair and adjustment.
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