1. Check:
- carburetor body
- float chamber
- jet housing
Cracks/damage → Replace.
2. Check: fuel passages
Obstruction → Clean.
![](https://motoinstruction.ru/img/yamaha/16/122426.jpg)
a. Wash the carburetor in a petroleumbased solvent. Do not use any caustic-carburetorcleaning solution.
b. Blow out all of the passages and jets with compressed air.
3. Check: float chamber body
Dirt → Clean.
4. Check: float chamber rubber gasket
Cracks/damage/wear → Replace.
5. Check: float
Damage → Replace.
![](https://motoinstruction.ru/img/yamaha/16/122427.jpg)
6. Check:
- needle valve (1)
- needle valve seat (2)
- O-ring (3)
Damage/obstruction/wear → Replace the needle valve, needle valve seat and O-ring as a set.
![](https://motoinstruction.ru/img/yamaha/16/122428.jpg)
7. Check:
- piston valve (1). Damage/scratches/wear → Replace.
- rubber diaphragm (2). Cracks/tears → Replace.
![](https://motoinstruction.ru/img/yamaha/16/122429.jpg)
8. Check:
- vacuum chamber cover (1)
- piston valve spring (2)
- plastic cap (3)
- O-ring (4)
- spring (5)
Cracks/damage → Replace.
![](https://motoinstruction.ru/img/yamaha/16/122430.jpg)
9. Check:
- jet needle (1)
- needle jet (2)
- main jet (3)
- pilot screw (4)
- pilot jet (5)
- main air jet (6)
- starter jet (7)
Bends/damage/wear → Replace.
Obstruction → Clean.
Blow out the jets with compressed air.
![](https://motoinstruction.ru/img/yamaha/16/122431.jpg)
10. Check: piston valve movement
Insert the piston valve into the carburetor body and move it up and down.
Tightness Replace the piston valve.
![](https://motoinstruction.ru/img/yamaha/16/122432.jpg)
11. Check.
- fuel feed pipes
- hose joint
Cracks/damage → Replace.
Obstruction → Clean.
Blow out the pipes with compressed air.
12. Check:
- fuel feed hoses
- fuel hoses
Cracks/damage/wear → Replace.
Obstruction → Clean.
Blow out the hoses with compressed air.