Synchronizing The Carburetor; Adjusting The Dashpot - Yamaha F30A Service Manual

FUEL

Synchronizing the carburetor

CAUTION:
Do not adjust the carburetors when they
are operating properly. Excessive adjust-
ment may cause poor engine perfor-
mance.
1. Remove the plugs 1, and then attach
the special service tool to the intake
manifold as shown.
Vacuum gauge 2: 90890-03094
2. Start the engine and warm it up for 10
minutes.
3. Attach the special service tool to spark
plug wire #1 3, and then check the
engine idle speed.
3
Digital tachometer: 90890-06760
4-17
Fuel system
1
2
S67C4034
S67C4035
Engine idle speed: 850 ± 50 r/min
4. Check the vacuum pressure of all cylin-
ders.
5. Turn the synchronizing screws 4 in
direction a or b until the specified vac-
uum pressure is obtained.
a b
NOTE:
• To increase the vacuum pressure, turn the
synchronizing screw in direction a.
• To decrease the vacuum pressure, turn the
synchronizing screw in direction b.
Vacuum pressure:
42.6 kPa (319.5 mmHg, 12.6 inHg)
6. Check the engine idle speed. Repeat
steps 3–5 if out of specification.

Adjusting the dashpot

1. Start the engine and warm it up.
2. Attach the special service tool to spark
plug wire #1 1.
1
4
S67C4036
S67C3033
67C3K11