21
Cylinder Exhaust Port
IMPORTANT
The cylinder exhaust port must be inspected and cleaned
of excess carbon every 3 months or 90 hours of operation
in order to maintain this engine within the emissions
durability period. ECHO strongly recommends that you
return your unit to your ECHO dealer for this important
maintenance service.
CARBURETOR ADJUSTMENT
Engine Break-In
New engines must be operated a minimum duration of two tanks of
fuel break-in before carburetor adjustments can be made. During the
break-in period your engine performance will increase and exhaust
emissions will stabilize. Idle speed can be adjusted as required.
High Altitude Operation
This engine has been factory adjusted to maintain satisfactory
starting, emission, and durability performance up to 1,000 feet above
mean sea level (MSL). To maintain proper engine operation above
1,000 feet MSL the carburetor must be adjusted by an authorized
ECHO service dealer.
IMPORTANT
If the engine is adjusted for operation above 1,000 feet MSL, the
carburetor must be re-adjusted when operating the engine below
1,000 feet MSL, otherwise severe engine damage can result.
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 (see page 4) 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.
1. Start engine and run for several minutes to reach operating
temperature.
2. Stop engine.
3. Start engine and turn the high-speed needle (A) rich (CCW) until
the engine runs between 13,500 and 14,500 RPM. Then turn the
low-speed needle (B) rich (CCW) until the engine does not
hesitate when accelerated.
DO NOT REMOVE LIMITER CAPS!
4. Idle Speed Adjustment.
• Turn “idle” speed adjustment screw (C) 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.
A
B
C
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.
