Yamaha F100D - Assembling the Power Unit

6D93G11
5-50
1
2
3
4
5
6
7
8
9
Assembling the power unit
1. Install the oil ring
1
, second ring
2
, and
top ring
3
onto the pistons with the “T”
marks
a
on the piston rings facing
upward.
2. Offset the piston ring end gaps as
shown.
CAUTION:
Do not scratch the piston or break the pis-
ton rings.
NOTE:
After installing the piston rings, check that
they move smoothly.
3. Install the upper bearing into the con-
necting rod
4
and the lower bearing into
the connecting rod cap
5
.
NOTE:
Install the bearings in their original positions.
4. Install the piston with the “UP” mark on
the piston crown facing towards the fly-
wheel magnet.
NOTE:
Apply engine oil to the side of the pistons and
piston rings before installation.
5. Install half of the bearings
6
into the cyl-
inder block
7
.
NOTE:
• Install the bearings in their original posi-
tions.
• Install the unified thrust bearing at the posi-
tion
b
shown.
S60C5A70
UP
#1,#4
#1
#2
#2
#5
#5
#4
#3
#3
45˚ 45˚
E
1
2
3
a
a
S60C5A80
E
5
4
Piston slider: 90890-06530
S60C5A90
S60C5B10
b
6
7
Cylinder block