Yamaha Wolverine YX70EPNG, Service Manual

Page: 287 / 503

CRANKSHAFT AND OIL PUMP
5-74
EBS30191
CHECKING THE CRANKSHAFT
1. Measure:
• Crankshaft width “a”
Out of specification
→
Replace the crank-
shaft.
2. Measure:
• Crankshaft runout “b”
Out of specification
→
Replace the crank-
shaft.
3. Measure:
• Big end side clearance “c”
Out of specification
→
Replace the crank-
shaft.
4. Check:
• Crankshaft sprocket
Damage/wear
→
Replace the crankshaft.
• Bearing
Cracks/damage/wear
→
Replace.
5. Check:
• Crankshaft journal
Scratches/wear
→
Replace the crankshaft.
• Crankshaft journal oil passage
Obstruction
→
Blow out with compressed air.
EBS30192
ASSEMBLING THE OIL PUMP
1. Lubricate:
• Inner rotor
• Outer rotor
• Oil pump shaft
(with the recommended lubricant)
2. Install:
• Oil pump housing “1”
• Oil pump outer rotor “2”
• Oil pump inner rotor “3”
• Oil pump shaft “4”
• Pin “5”
TIP
To install the oil pump shaft “4”, align the pin “5”
with the groove “a” in the inner rotor “3”.
3. Check:
• Oil pump operation
Refer to “CHECKING THE OIL PUMP” on
page 5-73.
EBS30193
INSTALLING THE CRANKSHAFT
1. Install:
• Balancer “1”
• Crankshaft “2”
NOTICE
ECB01890
Apply engine oil to each bearing to protect
the crankshaft against scratches and to
make installation easier.
TIP
• Install the balancer “1” and crankshaft “2” at the
same time.
• Align the hole “a” in the balancer with the
punch mark “b” on the crankshaft.
• Install the crankshaft with the crankshaft in-
staller pot “3”, crankshaft installer bolt “4”,
adapter (M16) “5”, and spacer (crankshaft in-
staller) “6”.
• Hold the connecting rod at top dead center
(TDC) with one hand while turning the nut of
the crankshaft installer bolt with the other. Turn
the crankshaft installer bolt until the crankshaft
assembly bottoms against the bearing.
Crank assembly width
65.68–65.76 mm (2.586–2.589 in)
Runout limit
0.030 mm (0.0012 in)
Big end side clearance
0.090–0.500 mm (0.0035–0.0197
in)
b b
a
c
Recommended lubricant
Engine oil
1
2
3
a
5
4
a