Echo CS-2511WES Service Manual

FUEL SYSTEM
33
CS-2511WES
251Ws
4-8 Adjusting carburetor (continued)
4-8-3Adjustingcarburetor
PI controller installed model has 2 mode; Carburetor
adjustment mode and Operation mode.
When adjusting carburetor, must be changed from
Operation mode to Carburetor adjustment mode in
the following steps.
1. Start engine without brake activated. Do not touch
throttle lever.
2. Warm up engine with fast idle for 120 seconds.
The speed should be within 6,000 - 10.000 r/min. If it
is not, adjust the speed by turning H mixture needle.
CAUTION: Chain will start to rotate during engine
warm-up with fast idle.
NOTE: Do not stop engine during carburetor adjust-
ment. If the engine is stopped, start above steps
from the beginning.
3. Warm up engine for 30 seconds alternating engine speed between WOT 5 seconds and idle 5 seconds.
4. Conrm to vary the idle speed by turning L mixture needle 1/4 turn clockwise. If the speed does not
vary, change the mode again.
NOTE: The idle engine speed returns to 3,200 r/min for a few second in Operation mode, when the
engine speed is deviated.
5. Adjust L mixture needle (B) using D-shaped tool (A) to reach maximum engine speed just before lean
drop off.
If chain starts to rotate during adjustment, decrease engine speed by turning throttle adjust screw (D)
counterclockwise untill chain stops and then readjust L mixture needle (B).
6. Set idle engine speed to 4,100 r/min by turning Throttle adjust screw (D). Engine speed should be
stable at 4,100 +/- 50 r/min after Throttle adjust screw adjustment.
7. Turn L mixture needle (B) counterclockwise reducing engine idle speed 800 r/min to set idle speed at
3,300 r/min. The engine idle speed ranges 3,200 - 3,400 r/min.
NOTE : Engine speed must be allowed to stabilize a minimum of 20 seconds after each adjustment of L
mixture needle to assure accurate tachometer readings.
8. Stop engine and restart engine. Verify engine idle speed ranges from 3,100 to 3,300 r/min, and WOT
engine speed ranges from 12,800 to 13,400 r/min. If the WOT speed is not within above range, return to
“4-8-2 Initial setting” and set H mixture needle again. If that does not work, adjust H mixture needle by 1/8
turn. Make sure the chain does not rotate when engine is idling. When nal adjustment is completed, the
engine should idle, accelerate smoothly, and attain WOT per above specications.
9. Conrm clutch engagement speed. If it is less than 1.25 times the idle speed, adjust the idle speed by
turning TAS counterclockwise.
NOTE: WOT engine speed in eld operation may vary from nal adjustment specications due to chang-
ing ambient conditions and fuel. Safe engine speed variances should be within the WOT and Idle engine
speed ranges listed in Section “1-2 Technical data”, otherwise the carburetor should be readjusted.
1
7
4
3
2
A
B
C
D

Echo CS-2511WES Specifications

General

Brand	Echo
Model	CS-2511WES
Category	Chainsaw
Language	English