Yamaha TW200N Service Manual page 43

CARBURETOR
6. Check:
• needle valve 1
• needle valve seat 2
Damage/obstruction/wear → Replace the
needle valve, needle valve seat and O-ring
as a set.
7. Check:
• O-ring 3
Damage/wear → Replace the needle valve,
needle valve seat and O-ring as a set.
8. Check:
• piston valve 1
Damage/scratches/wear → Replace.
• piston valve diaphragm 2
Cracks/tears → Replace.
9. Check:
• vacuum chamber cover 1
• piston valve spring 2
• jet needle holder 3
• jet needle spring 4
Cracks/damage → Replace.
10.Check:
• jet needle kit 1
• main jet 2
• main jet holder 3
• pilot jet 4
• starter plunger 5
Bends/damage/wear → Replace.
Obstruction → Clean.
Blow out the jets with compressed air.
11.Check:
• piston valve movement
Insert the piston valve into the carburetor
body and move it up and down.
Tightness → Replace the piston valve.
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CARB