Yamaha F100A - Cylinder Block Inspection; Piston Inspection

5-37
POWR
E
CRANKSHAFT AND PISTON/
CONNECTING ROD ASSY.
SERVICE POINTS
Cylinder block inspection
1. Measure:
● Cylinder bore
Out of specification → Rebore the cyl-
inder or replace the cylinder block.
NOTE:
Measure the cylinder bore in parallel and at
a right angle to the crankshaft. Then, aver-
age the measurements.
Standard
Wear
limit
Cylinder
bore “D”
79.000 ~ 79.020 mm
(3.110 ~ 3.111 in)
—
Taper
limit “T”
—
0.08 mm
(0.003 in)
Out of
round limit
—
0.08 mm
(0.003 in)
D = Maximum Dia. (D
1 ~ D6)
T = (maximum D
1 or D2) – (minimum D5
or D6)
D
20mm(0.8in)
D1 and D2
D3 and D4
D5 and D6
70mm(2.8in)
120mm(4.7in)
D2
D1
Piston inspection
1. Measure:
● Piston diameter
Out of specification → Replace the
piston.
Distance
a
Piston diameter
Standard
13 mm
(0.51 in)
78.928 ~ 78.949 mm
(3.1074 ~ 3.1082 in)
Oversize piston diameter:
Oversize 1: + 0.25 mm (0.001 in)