Yamaha F150A, Service Manual

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7-66
Crankcase
Checking the piston pin diameter
1. Measure the piston pin diameter “a”.
Checking the connecting rod small
end inside diameter and big end
inside diameter
1. Tighten the connecting rod bolts “1” to
the specified torques in 3 stages.
TIP:
• When checking the oil clearance, reuse the
removed connecting rod bolt.
• In the third tightening stage for the connect-
ing rod bolts “1”, mark the connecting rod
bolts and the connecting rod cap with iden-
tification marks “a”, and then tighten the
bolts 90° from the marks on the connecting
rod cap.
2. Measure the connecting rod small end
inside diameter “b” and big end inside
diameter “c”.
Checking the connecting rod big end
side clearance
1. Measure the connecting rod big end side
clearance “a”.
Checking the crankshaft
1. Measure the crankshaft journal diame-
ters “a”, crankpin diameters “b”, and
crankpin widths “c”.
Piston pin outside diameter “a”:
21.008–21.017 mm
(0.8271–0.8274 in)
Connecting rod bolt “1”:
1st: 13 N·m (1.3 kgf·m, 9.6 ft·lb)
2nd: 23 N·m (2.3 kgf·m, 17.0 ft·lb)
3rd: 90°
a
1
90˚
b
c
a
Connecting rod small end inside diameter
“b”:
21.022–21.037 mm
(0.8276–0.8282 in)
Connecting rod big end inside diameter
“c”:
53.025–53.045 mm
(2.0876–2.0884 in)
Connecting rod big end side clearance “a”:
0.14–0.31 mm (0.006–0.012 in)
a
a
a
b
c