Adjusting Carburetor - Yamabiko Echo SRM-222ES Service Data

8
2-3 Adjusting carburettor
(D)
(C)
Nylon line lengths
SRM-222ES(L) SRM-222ES(U)
Model name
T226S
Carburettor
180 mm
setting
Confi rming 145 mm
Make sure the nylon line cutter does not rotate when engine is at idle. Engine should start and accelerate smoothly.
8. After adjusting carburettor, insert and secure new plug(s) (E) P005-001270 deep in the needle holes
per the Emission Directive using limiter plug tool 91020 (C).
NOTE : WOT, and idle speed in field operation may vary from final adjustment specifications due to
changing ambient conditions, fuel, and engine loads. Safe engine speed variances should be within the
WOT and Idle speed ranges listed in Section 1-2, otherwise the carburettor should be readjusted.
SERVICE INFORMATION
(A)
(B)
(C)
(E)
(E)
GT-222ES
C226S F226S
180 mm 130 mm
- 145 mm
GT-222ES, SRM-222ES
SRM-222ES, T226S, C226S: Remove shield and
cut trimmer head line lengths to 180 mm.
GT-222ES, F226S: Cut trimmer head line lengths
to 130 mm with shield. (normal lengths : 145 mm
cut by shield knife.)
1. Start and warm engine for 3 minute alternating
engine speed between WOT for 50 seconds and
idle for 10 seconds.
2. Adjust Idle mixture needle (A) to reach maxi-
mum idle speed using 2.5 mm blade screwdriver.
3. Set Idle speed to 3,700 r/min by turning Idle
adjust screw (D). Engine speed should be stable at
3,700 +/- 50 r/min.
4. Turn Idle mixture needle anticlockwise to reduce
engine idle speed 1,400 r/min to set idle speed at 2,300
r/min. The idle speed range is 2,200 - 2,400 r/min.
5. Turn Idle adjust screw (D) clockwise to increase
idle engine speed to set idle at 3,000 r/min. The
idle speed range is 2,900 to 3,100 r/min.
NOTE : Engine speed must be allowed to stabilize a
minimum of 20 seconds after each adjustment of idle
mixture needle to assure accurate tachometer readings.
6. Adjust Hi speed mixture needle (B) to reach maximum
WOT engine speed.(max. approx. 8,000 r/min) Then turn
Hi speed mixture needle (B) anticlockwise to reduce WOT
engine speed 20 r/min (RANG : 10-30 r/min).
NOTE : Nylon line length should be 180 mm with-
out shield on SRM-222ES, T226S and C226S.
Nylon line length should be 130 mm with
shield on GT-222ES and F226S.
7. SRM-222ES(L), T226S : Stop engine and rein-
stall shield with knife, and restart engine and verify
engine idle speed ranges from 2,600 to 3,400
r/min, and expand and cut nylon line by shield
knife and WOT engine speed ranges from 9,000 to
10,000 r/min on SRM-222ES(L) and T226S, from
6,700 to 7,700 r/min on GT-222ES and F226S.
NOTE: Nylon line length should be 145 mm with shield.
SRM-222ES(U), C226S : Stop engine and reinstall
shield for 3-tooth blade (230 mm) and the blade.
Restart engine and verify engine idle speed ranges
from 2,600 to 3,400 r/min, and WOT engine speed
ranges from 10,500 to 11,500 r/min.
F226S, T226S, C226S