Selecting The Crankshaft Main Bearing; Assembling The Cylinder Block - Yamaha F30A Service Manual

POWR
6. Install the crankcase onto the cylinder
block, and then tighten the crankcase
bolts to the specified torques in 2 stages
and in the sequence shown.
5
C
1
9
4
B
8
F
E
NOTE:
• Apply engine oil to the threads of the crank-
case bolts.
• Do not turn the crankshaft until the crank-
shaft journal oil clearance measurement
has been completed.
Crankcase bolt 1–8 (M8):
1st: 15 N·m (1.5 kgf·m, 11.1 ft·lb)
2nd: 30 N·m (3.0 kgf·m, 22.1 ft·lb)
Crankcase bolt 9–F (M6):
1st: 6 N·m (0.6 kgf·m, 4.4 ft·lb)
2nd: 12 N·m (1.2 kgf·m, 8.9 ft·lb)
7. Gently remove the crankcase, and then
measure the width of the compressed
Plastigauge (PG-1) on each crankshaft
journal. Replace the main bearings if out
of specification.
NOTE:
When loosening the crankcase bolts, loosen
them in the opposite order used for tighten-
ing.
5-49
Power unit
6
D
2
0
3
A
7
E
E
S67C5145
Crankshaft journal oil clearance
(reference data):
0.012–0.044 mm
(0.0005–0.0017 in)
Selecting the crankshaft main
bearing
1. Check the stamped marks a, b, c, and
d on the cylinder block.
#4 #3
CCBC
CCBC
d c b a
NOTE:
The stamped marks a, b, c, and d indi-
cate crankshaft main bearings #1, #2, #3,
and #4 respectively.
2. Select the suitable bearing color e for
the main bearings from the table.
Stamped marks
a, b, c, and d
A
B
C

Assembling the cylinder block

1. Assemble the piston 1, connecting rod
2, piston pin 3, and piston pin clips 4.
#2 #1
e
S67C5147
Bearing color e
Blue
Black
Brown
67C3K11