Disassembling The Crankcase; Checking The Crankcase; Assembling The Crankcase - Yamaha MT-09 2021 Service Manual

EAS30389

DISASSEMBLING THE CRANKCASE

1. Place the engine upside down.
2. Remove:
• Crankcase bolt (×31)
TIP
• Loosen each bolt 1/4 of a turn at a time, in stag-
es and in a crisscross pattern. After all of the
bolts are fully loosened, remove them.
• Loosen the bolts in the proper sequence as
shown.
• The numbers embossed on the crankcase in-
dicate the crankcase tightening sequence.
1 2
13
11
17
23
22
25
24
14
15
2
1
3
3. Remove:
• Lower crankcase
ECA13900
NOTICE
Tap on one side of the crankcase with a soft-
face hammer. Tap only on reinforced por-
tions of the crankcase, not on the crankcase
mating surfaces. Work slowly and carefully
and make sure the crankcase halves sepa-
rate evenly.
4. Remove:
• Dowel pin
5. Remove:
• Crankshaft journal lower bearing
• Balancer shaft journal bearing
(from the lower crankcase)
TIP
Identify the position of each part very carefully so
that it can be reinstalled in its original place.
7
8
9
10
20
21
29
27
31
28 30 26
19 16
6
18
4 5
EAS30390

CHECKING THE CRANKCASE

1. Thoroughly wash the crankcase halves in a
mild solvent.
2. Thoroughly clean all the gasket surfaces and
crankcase mating surfaces.
3. Check:
• Crankcase
Cracks/damage → Replace.
• Oil delivery passages
Obstruction → Blow out with compressed air.
EAS30397

ASSEMBLING THE CRANKCASE

1. Lubricate:
• Crankshaft journal bearing inner surface
(with the recommended lubricant)
Recommended lubricant
2. Apply:
• Sealant
(onto the crankcase mating surfaces)
Yamaha bond No. 1215
Three bond No. 1215®
TIP
• Do not allow any sealant to come into contact
with the oil gallery or crankshaft journal bear-
ings, or balancer shaft journal bearings.
• Make sure that the sealant does not get into
31
the groove "a" in the crankcase.
5-65
CRANKCASE
Engine oil
90890-85505
a