- Oil pump driven gear "1". Cracks/damage/wear → Replace.
- Oil pump housing "2". Cracks/damage/wear → Replace the oil/water pump assembly.
![](https://motoinstruction.ru/img/yamaha/20/126696.jpg)
2. Measure:
- Inner-rotor-to-outer-rotor-tip clearance "a"
- Outer-rotor-to-oil-pump-housing clearance "b"
- Oil-pump-housing-to-inner-rotor-and-outer-rotor clearance "c"
Out of specification → Replace the oil/water pump assembly.
Inner-rotor-to-outer-rotor-tip clearance.
Less than 0.12 mm (0.0047 in).
Limit 0.20 mm (0.0079 in).
Outer-rotor-to-oil-pump-housing clearance 0.090-0.190 mm (0.00350.0075 in).
Limit 0.260 mm (0.0102 in).
Oil-pump-housing-to-inner-and-outer-rotor clearance 0.06-0.13 mm (0.0024-0.0051 in).
Limit 0.200 mm (0.0079 in).
![](https://motoinstruction.ru/img/yamaha/20/126697.jpg)
1. Inner rotor; 2. Outer rotor; 3. Oil pump housing
3. Check:
- Oil pump operation
Rough movement → Repeat steps (1) and (2) or replace the defective part(s).
![](https://motoinstruction.ru/img/yamaha/20/126698.jpg)