Use and Care Manual

26
CS-352
Every unit is run at the factory and the carburetor is set
in compliance with Emission Regulations. In addition,
the carburetor is equipped with “H” (High Speed) and
“L” (Low Speed) needle adjustment limiters that prevent
settings outside acceptable limits.
1. Before adjusting carburetor clean or replace air lter
and mufer “Spark Arrestor Screen”.
2. Make sure the bar and chain are properly adjusted.
3. Start engine and run several minutes to bring to oper-
ating temperature. Flash choke twice during warm-up
to clear any air from the fuel system.
4. Stop engine.
Turn “H” speed needle counterclockwise (CCW) to
stop.
Turn “L” speed needle midway between full clockwise
(CW) stop and CCW stop.
5. Idle Speed Adjustment:
• Start engine, turn “Idle” speed adjustment screw
CW until the saw chain begins to turn, then turn
screw out CCW until the saw chain stops turning.
Turn screw out, CCW, an additional 1/4 turn.
6. Accelerate to full throttle for 2 - 3 seconds to clear any
excess fuel in the engine, then return to idle.
Accelerate engine to full throttle to check for smooth
transition from idle to high speed.
If engine hesitates turn “L” needle CCW 1/8 turn and
repeat acceleration.
Continue adjustment until smooth acceleration results.
7. Check idle speed and reset if necessary as described
in item 5. If a tachometer is available idle speed should
be set to 3000 r/min.
WARNING
Cutting attachment must not move when unit is
idling.
CAUTION
When starting, idling adjustment speed should
be adjusted not to rotate the saw chain. Correct
idle speed is adjusted 3000 r/min. Or 1/4 turn CCW
from the point the chain stops moving.
When you experience trouble with the carburetor,
contact your dealer.
Idle adjusting screw
Low speed needle (L)
High speed needle (H)
CARBURETOR ADJUSTMENT
Engine Break-In
Newenginesmustbeoperatedaminimumduration
oftwotanksoffuelbreak-inbeforecarburetoradjust-
mentscanbemade.Duringthebreak-inperiodyour
engineperformancewillincreaseandexhaustemis-
sionswillstabilize.Idlespeedcanbeadjustedas
required.
High Altitude Operation
This engine has been factory adjusted to maintain sat-
isfactorystarting,emission,anddurabilityperformance
upto1,100feetabovesealevel(ASL)(96.0kPa).To
maintain proper engine operation and emission compli-
anceabove1,100feetASLthecarburetormay need to
be adjusted by an authorized ECHO service dealer.
IMPORTANT
Iftheengineisadjustedforoperationabove
1,100feetASL,thecarburetormustbere-
adjustedwhenoperatingtheenginebelow1,100
feetASL,otherwisesevereenginedamagemay
result.