Measuring And Adjusting The Float Height; Checking The Autochoke Assembly - Yamaha YJ50RN Service Manual

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1
CARBURETOR
EAS00499
MEASURING AND ADJUSTING THE FLOAT
HEIGHT
1. Measure:
• float height a
Out of specification → Replace the needle
valve.
Float height
15 ~ 17 mm (0.59 ~ 0.67 in)
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a. Remove the carburetor.
b. Hold the carburetor in an upside down posi-
tion.
c. Measure the distance from the mating sur-
face of the float chamber to the top of the
float.
d. If the float height is not within specification,
check the needle valve.
e. If either is worn, replace them as a set.
f. Install the carburetor.
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EAS00503

CHECKING THE AUTOCHOKE ASSEMBLY

NOTE:
@
When checking the autochoke assembly, the
ambient temperature must be lower than 45 °C
(113 °F).
1. Remove:
• carburetor
2. Check:
• autochoke assembly
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a. Connect a 3.3-mm hose 1 to the starter air
passage 2 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.
6 - 7
CARB
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