Carburetor Adjustment - Craftsman 358.350600 Instruction Manual

CARBURETOR ADJUSTMENT
'_WARNING: The chain will be
moving during most of this procedure.
Wear your protective equipment and
observe all safety precautions. During
the low speed mixture adjustment re-
check idle speed after each turn of the
screw. The chain must not move at idle
speed.
Carburetor adjustment is critical and if
done improperly can permanently
damage the engine as well as the car-
buretor. If you require further assis-
tance or are unsure about performing
this procedure, call our customer as-
sistance help line at 1-800-235-5878.
Old fuel, a dirty air filter, dirty fuel filter,
or flooding may give the impression of
an improperly adjusted carburetor.
Check these conditions before adjust-
ing the carburetor.
The carburetor has been carefully set
at the factory. Adjustments may be
necessary if you notice any of the fol-
lowing conditions:
• Chain moves at idle. See IDLE
SPEED-T under adjusting procedure.
• Saw will not idle. See IDLE SPEED-T
and LOW SPEED MIXTURE-L under
adjusting procedure.
• Engine dies or hesitates when it
should accelerate. See ACCELERA-
TION CHECK under adjusting
procedure.
• Loss of cutting power. See HIGH
SPEED MIXTURE - H under adjusting
procedure.
There are three adjustment screws on
the carburetor. They are labeled H, L,
and T. They are located in the area just
above the primer bulb.
ADJUSTING PROCEDURE
CAUTION: Do not force plastic limiter
caps on screws beyond the built-in
stops or damage will occur.
Initial Settings
1. Turn both mixture screws (L and H)
counterclockwise until they stop.
2. Turn the idle speed screw (T)
clockwise until it stops. Then turn it
counterclockwise 4 and 1/2 turns.
3. Start engine and let it run for 3 min-
utes, then proceed to adjust
screws according to the instruc-
tions below. If engine performance
at initial settings is acceptable, no
further adjustments are necessary.
If engine does not start, refer to the
TROUBLESHOOTING TABLE. If still
unable to remedy situation, call
1-800-235-5878.
Idle Speed-T
Allow engine to idle. If the chain
moves, idle is too fast. If the engine
stalls, idle is too slow. Adjust speed
until engine runs without chain move-
ment (idle too fast) or stalling (idle too
slow).
• Turn idle screw (T) clockwise to in-
crease engine speed.
• Turn idle screw (T) counterclockwise
to decrease engine speed.
Low Speed Mixture-L
Allow engine to idle. Then accelerate
the engine and note performance. If
engine hesitates, bogs down, or
smokes during acceleration, turn low
speed mixture screw (L) clockwise in
1/16-turn increments until performance
is satisfactory. Repeat this procedure
as necessary for proper adjustment.
After completing adjustments, check
for acceleration and chain movement
at idle. Reset if necessary.
High Speed Mixture-H
DO NOT operate engine at full throttle
for prolonged periods while making ad-
justments. Damage to the engine can
occur. Make a test cut. Based on per-
formance of the saw while cutting, ad-
just the high speed mixture setting in
1/16-turn increments as follows:
• Turn the high speed mixture screw (H)
clockwise until saw has good power in
the cut with no hesitation. Do not ad-
just by sound or speed, but judge by
how well the saw performs in the cut.
• Turn the high speed mixture screw
(H) counterclockwise if the saw has
speed, but dies in the cut or lacks
power in the cut.
After completing adjustments, check
for acceleration and chain movement
at idle. Reset if necessary.
Acceleration Check
If the engine dies or hesitates instead of
accelerating, turn the low speed mixture
screw (L) counterclockwise until you
have smooth acceleration with no chain
movement at idle.
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