Yamaha YZ250 2022, Owner'S Service Manual

Page: 199 / 274

CRANKCASE
5-37
EAM30147
DISASSEMBLING THE CRANKCASE
1. Remove:
•
Crankcase (right) “1”
(with the crankcase separating tool “2”)
TIP
•
Make appropriate bolts “3” as shown available
by yourself and attach the tool with them.
• Fully tighten the tool holding bolts, but make
sure the tool body is parallel with the case. If
necessary, one screw may be backed out
slightly to level tool body.
•
As pressure is applied, alternately tap on the
engine mounting boss and transmission
shafts.
NOTICE
ECA24690
Use soft hammer to tap on the case half. Tap
only on reinforced portions of case. Do not
tap on gasket mating surface. Work slowly
and carefully. Make sure the case halves
separate evenly. If the cases do not separate,
check for a remaining case bolt or fitting. Do
not force.
2. Remove:
•
Bearing “1”
TIP
• Remove the bearing from the crankcase by
pressing its inner race.
• Do not use the removed bearing.
EAM30150
CHECKING THE CRANKCASE
1. Wash:
• Crankcase
TIP
• Wash the crankcase in a mild solvent.
•
Remove any remaining gasket from the crank-
case mating surface.
2. Check:
•
Crankcase
Crack/damage

Replace.
•
Oil delivery passages
Obstruction

Blow out with compressed air.
EAM30152
ASSEMBLING THE CRANKCASE
1. Install:
•
Bearing “1”
(to the crankcase (left/right))
TIP
•
Apply the engine oil on the bearing.
• Install the bearing by pressing its outer race
parallel.
2. Install:
• Oil seal (left) “1”
•
Oil seal (right) “2”
TIP
•
Apply the lithium-soap-based grease on the oil
seal lip.
•
Install the oil seal with its manufacture’s marks
or numbers facing outward.
Crankcase separating tool
90890-01135
Crankcase separator
YU-01135-B
100 mm
Ne w
Ne w
Ne w