Briggs & Stratton 243434 - Manual (Page 4)

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CLEAN AND ADJUST CONTACT POINTS
Remove cover. Clean points with a carborundum con­
tact point stone. Then insert a hard finished card or
piece of paper and close and open points. The paper
will absorb any dirt or filings on the points. Adjust
breaker points as follows:
a. Rotate crankshaft until points open to widest gap,
b. Loosen lock_ nut illustrated o e s o w until it is just
snug.
c. Rotate breaker point screw to obtain .020" gap.
d. When gap is .020" tighten locknut.
e. Replace breaker box cover.
CLEAN SPARK PLUG — Clean and reset gap at .030*
every 100 hours of operation.
CAUTION: Blast cleaning of spark plugs In machines
that use abrasive grit is not recommended. Spark plugs
should be cleaned by scraping or wire brushing and
washing with a commercial solvent or gasoline.
DRAIN FUEL TANK AND CLEAN FUEL FILTER
Loosen thumb screw below filter bowl. Remove and
clean filter bowl and screen. Open shut-off valve to
see If fuel flows freely from the tank.' IMPORTANT: If
you find a gummy, varnish-like substance use alcohol
or acetone to dissolve it.
TURN BREAKER POINT SCREW
CLOCKWISE TO INCREASE GAP
CONDENSER
Clean and Adjust Contact Points
Section
, 4 ,
A S
CAiiUiETOi ADJUSTMENTS
Minor carburetor adjustment may be required to com­
pensate for differences in fuel, temperature, altitude
and load.
Initial Adjustment
Turn needle valve c l o c k w i s e until it just closes, —
CAUTION: Valve may be damaged by turning It in
too far.
Now open needle valve 1-1/2 turns counterclockwise.
Close idle valve In same manner and open It 1 /2to3/4
turns. This initial adjustment will permit the engine
to be started and warmed up prior to final adjustment.
Final Adjustment Turn needle valve in until engine misses (lean mixture), then turn it out past smooth operating
point until engine runs unevenly (rich mixture). Now turn needle valve to the mid-point totwstn rich iid itin
so the engine runs smoothly. Hold throttle at idle position, set Idle speed adjusting screw until fist iilt is
obtained (1200 RPM). Hold throttle in idle position and turn Idle valve in (lean) and out (rich) until tififit idles
smoothly. Then reset idle speed so that engine Idles at 1200 RPM. Release throttle — enqiiit ilcild icctltritt
without hesitation or sputtering. If engine does not accelerate properly, re-adjyst
1 »-. a siif|iitlf
richer mixture.