24
CARBURETOR
ADJUSTMENT
Non Emission Models (without limiter caps)
Level 2.
Tools required: Screwdriver, Tachometer (ECHO P/N 99051130017).
NOTE
If carburetor has limiter caps follow "Carburetor Adjustment" procedures for Type 1E models on previous page.
Basic Setting
1.
Stop engine and turn both LO (B) and HI (A) needles in, CW until
they stop and are lightly seated.
IMPORTANT
DO NOT over tighten needles. Forcing them to tighten will damage
the carburetor.
2.
Turn LO needle (B) out, CCW 1-1/4 turns. Turn HI needle (A) out
CCW 2-3/4 turns.
Fine Tuning
(Requires Accurate Tachometer ECHO P/N 99051130017)
1. Start engine and allow to warm to operating temperature (minimum 2 -
3 minutes) varying engine speed from idle to full throttle.
2. Always begin fine tuning with LO needle.
a. Lean drop-off - With engine idling, turn LO (B) needle slowly
CW (in) to lean drop-off point. RPM will increase, then
abruptly drop-off. (1) Note this position.
b. Rich drop-off - With engine idling, slowly turn LO (B) needle
CCW (out) to rich drop-off point. RPM will increase then
gradually slow and drop-off. (2) Note this position.
c. Final setting - Set needle at mid point between lean rich drop-
off points. (3)
d. Turn 1/8 turn CCW (out) making mixture slightly richer. (4)
3. High speed adjustment.
Adjust HI needle (A) with tachometer to achieve the specifications
found on page 12 "Specifications" of this manual.
4. Check idle speed and reset if necessary. Using a tachometer, idle
speed should be set to the specification found on page 12 "Specifi-
cations" of this manual.
WARNING
DANGER
When carburetor adjustment is completed, the cutting attachment
should not turn at idle, otherwise serious personal injury may
result.
Idle Speed Adjustment
Turn "idle" speed adjustment screw (C) CW (clockwise) until cutting
attachment begins to turn, then turn screw out CCW (counter clock-
wise) until attachment stops turning. Turn screw out, CCW an addi-
tional 1/4 turn.
WARNING
DANGER
Cutting attachment must not turn when unit is idling, otherwise
serious personal injury may result.
