Checking The Piston Pin Diameter; Checking The Connecting Rod Small End Inside Diameter And Big End Inside Diameter; Checking The Connecting Rod Big End Side Clearance; Checking The Crankshaft - Yamaha F150A Service Manual

Checking the piston pin diameter

1. Measure the piston pin diameter "a".
a
Piston pin outside diameter "a":
21.008–21.017 mm
(0.8271–0.8274 in)
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".
a
90˚
1
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°
b
c
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)
Checking the connecting rod big end
side clearance
1. Measure the connecting rod big end side
clearance "a".
a
Connecting rod big end side clearance "a":
0.14–0.31 mm (0.006–0.012 in)

Checking the crankshaft

1. Measure the crankshaft journal diame-
ters "a", crankpin diameters "b", and
crankpin widths "c".
7-66
Crankcase
a
a
b
c