Yamaha WR250F(P), Owner'S Service Manual

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ENG
OIL PUMP
INSPECTION
Oil pump
1. Inspect:
●
Oil pump drive gear 1
●
Oil pump drive shaft 2
●
Rotor housing 3
●
Oil pump cover 4
Cracks/wear/damage
→
Replace.
1
3
2
4
2. Measure:
●
Tip clearance
a
(between the inner rotor 1 and outer
rotor 2 )
●
Side clearance
b
(between the outer rotor 2 and rotor
housing 3 )
●
Housing and rotor clearance
c
(between the rotor housing 3 and
rotors 1 2 )
Out of specification
→
Replace the oil
pump assembly.
Tip clearance
a
:
0.12 mm or less
(0.0047 in or less)
<Limit>: 0.20 mm (0.008 in)
Side clearance
b
:
0.09 ~ 0.17 mm (0.0035 ~ 0.0067 in)
<Limit>: 0.24 mm (0.009 in)
Housing and rotor clearance
c
:
0.03 ~ 0.10 mm (0.0012 ~ 0.0039 in)
<Limit>: 0.17 mm (0.0067 in)
3. Check:
●
Unsmooth
→
Repeat steps #1 and #2
or replace the defective parts.