Yamaha YB50, Service Manual

Page: 98 / 161

CARB
CARBURETOR
5-6
EAS00503
CHECKING THE AUTOCHOKE UNIT
NOTE:
When checking the autochoke unit, the
ambient temperature must be lower than 45°C
(113°F).
1. Remove:
• carburetor
2. Check:
• autochoke unit
a. Connect a 3.3 mm hose to the starter air
passage and blow into the hose.
NOTE:
When the starter plunger is open, air should
come out of the other side of the starter air
passage.
3. Check:
• autochoke unit
a. Connect the autochoke unit leads to a
12.0 V battery for five minutes.
b. Connect a 3.3 mm hose to the starter air
passage and blow into the hose.
Starter plunger Perform step (3)
opens
Starter plunger Replace the auto-
closes choke unit.
Positive batter lead yellow/red
Negtive battery lead black
Starter plunger Replace the auto-
opens choke unit.
Starter plunger Autochoke is OK.
closes