SERVICE INFORMATION
CSG-7410ES
EC741S
3
1-2 Technical data
Engine
Compression pressure
MPa (kgf/cm
2
) (psi)
0.99 (10.1) (143)
Clutch engagement speed
r/min
3,800
Ignition system
Spark plug gap
mm(in)
0.6 - 0.7 (0.024 - 0.028)
Spark test
Tester gap w/ spark plug
mm(in)
4.0 (0.16)
Tester gap w/o spark plug
mm(in)
6.0 (0.24)
Secondary coil resistance
kΩ
1.5 - 2.5
Pole shoe air gaps
mm(in)
0.3 - 0.4 (0.012 - 0.016)
Ignition timing
at 2,700 r/min
°BTDC
18
at 9,000 r/min
°BTDC
30
Carburetor
Test Pressure, minimum
MPa (kgf/cm
2
) (psi)
0.05 (0.5) (7.0)
Metering lever height
mm(in)
Flush with diaphragm seat
Tool to adjust mixture needles
D-shaped tool (L) P/N X645-000031
Carburetor adjustment
Fuel type
Mixed two-stroke fuel Premixed alkylate fuel
Preparation
Remove cutter.
1) Initial setting
H mixture needle
turn out
3 1/2
3 3/8
L mixture needle
turn out
2
Throttle adjust screw turn out*
1
2 1/2
Engine warm-up
Idle - WOT : Total
sec.
10 - 5 : 120
2) Find idle maximum speed
Adjust L mixture needle to maximum idle speed*
2
3) Set idle maximum speed w/ TAS
r/min
3,700
3,750
4) Set idle speed by turning Lmixture needle CCW
When
carburetor or
diaphragm is
brand-new
2,800
When
carburetor or
diaphragm is
brand-new
2,800
r/min
3,300
2,800
5) Verify final engine speed with standard equipment
Idle:
3,100 - 3,400
Idle: 2,600 - 3,000
r/min
6) Verify clutch engagement speed
Confirm clutch engagement speed.
If it is less than 1.25 times the idle speed,
adjust the idle speed by turning TAS CCW.
BTDC:
Before top dead center.
WOT:
Wide open throttle
CCW:
Counterclockwise
TAS:
Throttle adjust screw
*
1
Turn TAS clockwise until its head touches boss. Then turn TAS counterclockwise.
*
2
If clutch engages during adjustment process 2), decrease engine speed by turning TAS CCW until clutch
disengages and then redo 2).
