Carburetor Adjustment - Echo CS-301 Instruction Manual

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.
BEFORE MAKING ADJUSTMENTS:
• The correct spark plug must be clean and properly
gapped.
• The air filter element must be clean and properly
installed.
• The muffler spark arrestor screen and exhaust port
must be clear of carbon.
• The standard bar and chain combination must be
installed to the power head, and properly
tensioned.
LOW ALTITUDE ADJUSTMENT
Engines that have been adjusted to operate at high
altitudes must be readjusted to operate properly at
altitudes below 2000 feet.
B
1. Start engine and run for several minutes to reach operating
temperature.
2. Stop engine. Remove grommet cover (A) over "H" and "L"
limiter needles.
3. Start engine and turn the high-speed needle rich (CCW)
until the engine runs between 11,500 and 12,000 RPM.
Then turn the low-speed needle rich (CCW) until the
engine does not hesitate when accelerated.
DO NOT REMOVE LIMITER CAPS!
4. Idle Speed Adjustment.
• Turn "idle" speed adjustment screw (B) CW until the saw
chain begins to move, then turn the screw CCW until saw
chain stops moving. Turn screw CCW an additional 1/4
turn.
5. Accelerate to full throttle for 2-3 seconds to clear excess
fuel from engine then return to idle. Accelerate to full
throttle to check for smooth transition from idle to full
throttle. If engine stops or stalls after full warm up return
the unit to your authorized ECHO dealer for adjustment.
6. Install grommet cover (A) over "H" and "L" limiter needles.
HIGH ALTITUDE ADJUSTMENT
High altitude adjustment may be required for proper operation
of this engine above 2000 feet.
1. Start engine and run for several minutes to reach operating
temperature.
A
2. Stop engine. Remove grommet cover (A) over "H" and "L"
limiter needles.
3. Start engine and turn the HI speed needle lean (CW) until
the engine runs between 11,500 and 12,000 RPM. Then
turn the LO speed needle lean (CW) until the engine does
not hesitate when accelerated.
DO NOT REMOVE LIMITER CAPS!
4. Idle Speed Adjustment.
• Turn "idle" speed adjustment screw (B) CW until the saw
chain begins to move, then turn the screw CCW until saw
chain stops moving. Turn screw CCW an additional 1/4
turn.
5. Accelerate to full throttle for 2-3 seconds to clear excess
fuel from engine then return to idle. Accelerate to full
throttle to check for smooth transition from idle to full
throttle. If engine stops or stalls after full warm up return
the unit to your authorized ECHO dealer for adjustment.
6. Install grommet cover (A) over "H" and "L" limiter needles.
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