Checking The Crankshaft; Installing The Crankshaft Bearings - Yamaha EK40G Service Manual

Checking the crankshaft

1. Measure the crankshaft widths a and b.
Repair or disassemble the crankshaft if
out of specification.
2. Measure the connecting rod small end
axial play. Replace the bearing and con-
necting rod if above specification.
Crankshaft width a:
61.40–61.45 mm
(2.4173–2.4193 in)
Crankshaft width b:
41.38–41.60 mm
(1.6291–1.6378 in)
Connecting rod small-end axial play
limit:
2.0 mm (0.08 in)
3. Measure the crankshaft runout. Repair or
disassemble the crankshaft if above
specification.
c
c
c
Crankshaft runout limit c:
0.03 mm (0.0012 in)
Crankshaft aligner:
90890-03107
6H95G11

Installing the crankshaft bearings

1. Install the upper and lower bearings
using the bearing pressure C 1 and a
press.
1
NOTE:
9 Install the upper bearing so that the manu-
facture identification mark a faces the fly-
wheel magnet side.
9 Install the lower bearing so that the dowel
b faces the flywheel magnet side.
Bearing pressure C 1:
2. Slowly turn the crankshaft and connect-
ing rods. If it does not turn smoothly, dis-
assemble the crankshaft and adjust or
replace any parts as necessary.
6B450790
90890-02393
Crankcase
1
a
2
b
3
6B450780
4
5
6
7
8
6B450800
9
5-36