Echo CSG-7410 Operator's Manual page 27

Carburetor Adjustment
Idle adjusting screw
High speed needle (H)
High Altitude Operation
This engine has been factory adjusted to maintain
satisfactory starting, emission, and durability
performance up to 1100 feet above sea level (ASL)
(96.0 kPa).
To maintain proper engine operation and emission
compliance above 1100 feet ASL the carburetor
may need to be adjusted by an authorized ECHO
service dealer.
IMPORTANT
If the engine is adjusted for operation above
1100 feet ASL, the carburetor must be
readjusted when operating the engine below
1100 feet ASL, otherwise severe engine damage
may result.
Low speed needle (L)
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
filter and muffler "Spark Arrestor Screen".
2. Install the wheel.
3. Start engine and run several minutes to bring to
operating temperature.
Flash choke twice during warm-up to clear any
air from the fuel system.
4. Stop engine.
Turn "L" speed needle counterclockwise (CCW)
to stop.
Turn "H" 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 wheel begins to turn, then
turn screw out CCW until the wheel stops
turning.
Turn screw out, CCW, an additional 1 + ½
turn.
Cutting attachment must not move when unit
is idling.
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.
7. Check idle speed and reset if necessary as
described in item 5.
If a tachometer is available idle speed should be
set to 2800 rpm.
When starting, idling adjustment speed
should be adjusted not to rotate the wheel.
Correct idle speed is adjusted 2800 rpm.
Or 1 + ½ turn CCW from the point the wheel
stops moving.
When you experience trouble with the
carburetor, contact your dealer.
27
WARNING
CAUTION
CSG-7410