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E. CARBURETOR ADJUSTMENTS
_e The carburetor has been adjusted at the fac-
tory for sea level conditions. Adjustment may
become necessary if the unit is used at
significantly higher altitudes or if you notice.
any of the following conditions:
--Chain moves with the engine at idle speed.
_Loss of cutting power which is not cor-
• rected by air filteror muffler semen clean-
• ing.
m Engine dies or hesitates when it should
accelerate.
r:epermanent damage will occur to the engine if
..... incorrect carburetor adjustments are made. it
.... is best to let your Sears Service Center make
r "carburetor adjustments. If you choose to
make the adjustment yourself, follow the pro-
cedure below very carefully.
I - WARNING!
The-chain maybe moving during this procedure.
Wear your protective gear and observe all of the
• safety precautions.
1. PREPARATION
....... __a.Stop engine.
,b. Use a fresh fuel mixture with proper
gasoline/oil ratio.
c. Place the saw on a.solid, flat surface and
,make sure the chain will not contact any
....object.
d. Locate the three (3) Carburetor adjusting
screws located on the fan housing side of
the saw. Figure 54.
e. Turn the Low Speed Mixture Screw and the
,:• High Speed Mixture Screw clockwise
_: just until they stop. Do not turn the screws
L_:: until they are tight as you may damage
the needle seats.
f. Turn the Low SpeedMixtum Screw and the
High Speed Mixture Screw one full turn
.... counterclockwise AP_
!_2.'IDLE SPEED ADJUSTMENT--i
a. Start the engine aittl allow to idle.
= b. Adjust if the engine dies or stops by turning
.... the Idle Speed Screw • 1t2 turn clockwise
NOTE: To ;ncrease idle speed, turn the Idle
Speed Screw clockwise _ . To
decrease idle speed, turn the Idle Speed
...... Screw counterclockwise
"LOW HIGH
\ SPEED SPEED
ADJ. ADJ.
IDLE
SPEED ADJ. SCREW _ \
• Figure 54
c. Run the engine for a few minutes to bring it
up to operating temperature.
NOTE: The engine must be at operating
temperature for proper adjustments to be
made.
3. LOW SPEED MIXTURE ADJUSTMENT
a. Turn the Low Speed Mixture Screw slowly
• clockwise _ until the RPM Starts to
drop. Note the position.
b. Turn the Low Speed Mixture Screw coun-
terclockwise _ untilthe RPM speeds
up and starts to drop again. Note the posi-
tion.
c. Set the Low Speed Mixture Screw at the
mid-point between the two positions.
4. IDLE SPEED ADJUSTMENTBII
a. Allow engine toidle.
............ b._Adjust if the chain is turning by turning the
Idle SpeedScrew counterclockwise _ .
c. Squeeze the throttle trigger;, The saw
should accelerate without hesitating.
NOTE:It may be necessary to recheck the
low speed mixture setting after the idle
speed has been.reduced by repeating "Low
Speed Mixture Adjustment" as in step 3
above.
5, HIGH SPEED MIXTURE ADJUSTMENT
a. Make a test cut.
b. Adjust if the saw smokes or seems to have
low power in the test cut by turning the
High Speed Mixture Screw 1116th of a turn
clockwise
c. Repeat test cut.
d. Repeat adjustment until the saw runs
smoothly. -_
!CAUTION:JNev_r set the High Speed Mixture
Screw less than 7/8 tum open. This is tOOlean
- _:-a s_tting and:will ruin your engine.!
6. IDLE SPEED ADJUSTMENT--Ill
Recheck for proper idle mixture setting.
NOTE: It may be necessary to_ repeat Idle
Speed Adjustment-I and Low Speed Mixture
Adjustment. .- .
7. CHECK ACCELERATION
Adjust if there is a slight hesitation, by turn-
ing the Low Speed Mixture Screw 1116 of a
turn at a time counterclockwise _ un-
til you have smooth acceleration.
NOTE: Check to be sure'the chain is not turn-
ing when engine is idling, tf chain moves at
idle speed, repeat Idle Speed Adjustment-ll.
,21
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