Checking The Crankshaft; Checking The Connecting Rod Oil Clearance - Yamaha F4B Service Manual

POWR
e
c
Connecting rod small end inside diameter
e:
15.015–15.029 mm
(0.5911–0.5917 in)
Connecting rod big end inside diameter f:
28.000–28.015 mm
(1.1024–1.1030 in)
Connecting rod cap bolt a:
1st: 6 N·m (0.6 kgf·m, 4.4 ft·lb)
2nd: 12 N·m (1.2 kgf·m, 8.9 ft·lb)

Checking the crankshaft

1. Check the crankshaft gear a. Replace
the crankshaft if damaged or worn.
2. Measure the crankshaft journal diameter
b and c, crankpin diameter d, and
crankpin width e.
c
e
7-43
Power unit
b
f
d
a
a
a
b
d
Crankshaft journal diameter (cylinder block
side) b:
24.980–24.993 mm
(0.9835–0.9840 in)
Crankshaft journal diameter (crankcase
side) c:
24.982–24.994 mm
(0.9835–0.9840 in)
Crankpin diameter d:
27.969–27.984 mm
(1.1011–1.1017 in)
Crankpin width e:
21.000–21.100 mm
(0.8268–0.8307 in)
3. Measure the crankshaft runout.
Crankshaft runout: 0.020 mm (0.0008 in)
Checking the connecting rod oil
clearance
1. Clean the connecting rod, connecting rod
cap, and crankpin.
2. Place a piece of Plastigauge (PG-1) onto
the crankpin
crankshaft.
a,
parallel to
a
the