I I | I | IIIIIIIII[IIIIIIIIII | I I II | I | II IIIIII | I | llll | llIllll |
D. CARBURETOR ADJUSTMENTS
•Poor engine performance can bea result of other causes such as dirty air filter, carbon
Chart" before proceeding with carburetor adjustments.
•Forthe best results,
•The carburetor has been adjusted at the factory for sea level conditions. Adjustmentsmay become necessary if the unit is used at s{gnificantlyhigher altitudes orif you noticeany ofthe following conditions:
NOTE: Be sure to properly prepare the saw as described in "1. Preparation" below, before making any adjustments.
--Saw will not idle. See "2. Idle Speed Adjust- ment" and "3. Low Speed Mixture Adjust- ment."
--Engine dies or hesitates when it should accel- erate. See "4. Acceleration Adjustment."
--Loss of cutting power which is not corrected by air filter cleaning. "See" 5. High Speed Mix- ture Adjustment."
I CAUTION:I Permanent damage will occur to any
•If the unit will not operate properlyafter making these adjustments, take the unit to a qualified service dealer.
WARNING
The chain will be moving during most ofthis procedure. Wear your protective gear and observe all safety precautions.
1.PREPARATION
a.Stop engine.
b.Use a fresh fuel mixture with proper gasolinel oil ratio.
c.Place the saw on asolid, flatsurfaceand makesure the chain will not contact any object.
d.Locate the three (3) carburetor adjusting screw openings to the right ofthe air filtercover.Figure 40.
e.Start the engine and allow engineto idle 3 minutes to warm up. The engine must be at operating
temperature for proper adjustments to be made.
IDLE
Figure 40
2.IDLE SPEED ADJUSTMENT
a.Allow engine to idle.
b.AdjustIdle Speed Screw untilenginecontinuesto
run withoutstalling and withoutthechain moving.
--Turn screw clockwise _ to increase
engine speed ff engine stallsor dies.
turning.
c. No further adjustments are necessary if the chain does not move at idle speed and if perfor- mance is satisfactory.
_ILWARNING
Recheck idle speed after each adjustment below. The chain must not move at idle speed to avoid serious injury.
3. LOW SPEED MIXTURE ADJUSTMENT
a, | Allow engine to idle. |
| |
b | Turn the Low | Speed Mixture Screw | slowly |
| clockwise _ | until the RPM starts | to drop. |
| Note the position,. |
|
c. Turnthe | Low Speed Mixture Screw counterclock- |
wise _ | untilthe RPM speeds up and starts |
to drop again. Note the position. | |
d. Set the | Low Speed Mixture Screw at the mid- |
point between the two positions.
4.ACCELERATION ADJUSTMENT
Ifengine dies or hesitates insteadof accelerating, turn the LOwSpeed Mixture ScR,w 1/16of aturn at atime
counterclockwise _ until you have smooth acceleration.
5.HIGH SPEED MIXTURE ADJUSTMENT
I CAUTION:] Adjustments as small as 1/16 of a
turn can affect engine performance. It is impor- tant to turn the screw only 1/16of a turn per adjust- ment and test the performance of the saw before making further adjustments.
a.Make a test cut.
b.Adjust the High Speed Mixture Screw 1/16of aturn as follows:
Clockwise _ | if saw smokes or loses power. | ||
Counterclockwise | _ | if the saw has speed | |
| out of the cut but lacks power in the cut. |
c.Repeat test cut.
d.Continue 1116of a turn adjustments until the saw runs smoothly in cut.
tCAUTION: ] Atoo lean high speed setting (clock-
wise _ adjustment) will cause engine damage to any 2+cycle engine from overheating and lackof lubrication. Never set the high speed
mixture screw so far clockwise _ that you have high speed but lack power while cutting. An effective approach follows:
engine loses power while cutting. |
|
in 1/16 of a |
turn increments only until the engine has power while cutting.
NOTE: If the unit will not operate properly after
making these adjustments, take the unitto a qualified
service dealer.
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