Craftsman 247.799890 Chipper User Manual


 
The carburetor may need re-adjusting if engine lacks
power or does not idle properly. If adjustments are
needed, proceed as follows.
Close needle valve (see figure 17) clockwise
(F_) finger tight only. Forcing may cause damage.
Then open 1-1/2 turns counterclockwise (f").
Start engine and allow to warm for five minutes.
With throttle in FAST position, close needle valve
clockwise (_) until engine starts to lose speed
(lean mixture). Then slowly open needle valve
counterclockwise (v-_) until engine JUST BEGINS
to run unevenly. This mixture should be rich
enough for best performance under load.
Place throttle control in IDLE position.
If engine idles, no further adjustment is necessary.
If engine idles too fast, turn idle speed adjusting
screw counterclockwise (_'_) until slower speed is
obtained.
If engine dies, turn idle speed adjusting screw 1/4
turn clockwise (,'-_). Place throttle control in FAST
position and restart engine.
Move throttle control to IDLE position. If engine
does not idle, repeat third step.
Test the engine by using the chipper-shredder. If
engine tends to stall or die out, it usually indicates
that the mixture is slightly lean and it may be nec-
essary to open (r--_) the needle valve slightly to
provide a richer mixture. This richer mixture may
cause a slight unevenness in idling.
Idle Speed
ustin_
Throttle
Throttle
Needle Valve
FIGURE 17.
ENGINESPEED
Your engine speed has been factory set. Do not
attempt to increase engine speed or it may result in
personal injury. If you believe the engine is running
too fast or too slow, take your chipper-shredder to the
nearest SEARS Service Center for repair and adjust-
ment.
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