Echo GT-2150 Operator's Manual page 21

Low speed mixture
adjusting screw (L)
High speed mixture
adjusting screw (H)
IDLE SPEED ADJUSTMENT
Turn idle speed adjuster clockwise until cutting
attachment begins to turn, then turn screw out
anticlockwise until cutting attachment stops turning.
Turn screw out, anticlockwise, and additional 1/4
turn.
CAUTION
Cutting attachment must not turn when unit
is idling.
BASIC SETTING
1. Stop engine and turn both low (L) and high (H)
speed mixture adjusters in, clockwise until they
stop and are lightly seated.
CAUTION
DO NOT over tighten (L) / (H) adjusters.
Forcing them to tighten will damage the
carburettor.
2. Turn low speed mixture adjuster (L) out,
anticlockwise 1 and
Turn high speed mixture adjuster (H) out
anticlockwise 1 and
FINE TUNING
(Requires Accurate Tachometer)
1. Start engine and allow to run at high idle until
warm.
2. Adjust idle speed if necessary ( 2,500 to 3,000
r/min ).
3. Always begin fine tuning with low speed
mixture adjuster (L).
Idle speed adjuster (T)
1 / turn.
2
1
/ turn.
2
4. Slowly turn (L) adjuster clockwise, try to reach
maximum idle speed.
5. Turn (L) adjuster anticlockwise 1/8 to 1/4 turn.
6. Turn idle speed adjuster clockwise until cutting
attachment begins to turn.
7. Turn idle speed adjuster anticlockwise 1/2 turn
or until cutting attchment stops.
HIGH SPEED ADJUSTMENT
CAUTION
Improper high speed mixture adjustment
can result in lean opration and consequent
severe engine damage.
1. While engine running at full throttle, turn (H)
adjuster slowly clockwise until engine runs
smoothly under no road.
CAUTION
Do not run engine on full throttle longer than
5 to 6 seconds during high speed mixture
adjuster (H) adjustment to avoid damage to
engine.
2. Turn (H) adjuster anticlockwise 1/8 turn to
obtain optimum fuel for full power under the
load conditions.
3. After the high speed adjustment has been
completed, and should the engine hesitate
during acceleration from idle to full throttle, turn
(H) adjuster anticlockwise until smooth
acceleration is obtained.
Make sure that the final engine speed does not
exceed 11,500 r/min.
CAUTION
The engine will overheat when the high
speed mixture adjuster (H) is adjusted to the
lean condition reducing engine life.
21 GT-2150/2150S