Yamaha F40B - Installing the Carburetor; Adjusting the Pilot Screw

FUEL
Fuel system
4-15 67C3K11
Installing the carburetor
1. Install the carburetor joint assembly 1,
carburetor assemblies 2, throttle link
plate 3, and plate 4, and then tighten
the bolts 5 to the specified torque.
2. Install the intake silencer 6, and then
tighten the bolts 7 and 8 to the speci-
fied torque.
NOTE:
The intake silencer bolt 8 is different from
the bolts 7 and has a flat head.
3. Install the carburetor unit 9, and then
tighten the bolts 0 and A to the speci-
fied torque.
4. Connect the Prime Start leads B.
5. Connect the throttle link rod C to the car-
buretor throttle lever.
NOTE:
To adjust the throttle link rod, see “Adjusting
the throttle link” (3-8).
6. Adjust the engine idle speed.
NOTE:
If the carburetor has been disassembled and
assembled, adjust the pilot screw, and then
adjust the engine idle speed. See “Adjusting
the pilot screw” (4-15).
Adjusting the pilot screw
1. Adjust the throttle stop screw.
NOTE:
If the carburetor was disassembled, turn the
throttle stop screw in until it contacts the car-
buretor throttle lever, and then turn it in about
1/4–1/2 turn to tighten it temporarily.
2. Start the engine and warm it up.
3. Attach the special service tool to spark
plug wire #1.
T
R
.
.
Carburetor assembly bolt 5:
8 N·m (0.8 kgf·m, 5.9 ft·lb)
Intake silencer bolt 7 and 8:
8 N·m (0.8 kgf·m, 5.9 ft·lb)
S67C4039
77
7
5
5
3
6
5
8
4
2
1
2
T
R
.
.
Carburetor unit bolt 0:
8 N·m (0.8 kgf·m, 5.9 ft·lb)
Intake silencer bolt A:
8 N·m (0.8 kgf·m, 5.9 ft·lb)
Digital tachometer: 90890-06760
S67C4029
0
0
B
C
A
9