Yamaha EK40G, Service Manual

Page: 84 / 200

Removing the crankcase
1. Remove the crankcase bolts in the
sequence shown.
NOTE:
Insert a flat-head screw driver between the
pry tabs to pry off the crankcase.
Removing the crankshaft assembly
and oil seal housing
1. Remove the crankshaft assembly and oil
seal housing.
Checking the cylinder bore
1. Measure the cylinder bore (D
1
— D
6
) at
measuring points
a
,
b
, and
c
, and in
direction
d
(D
1
, D
3
, D
5
), which is parallel
to the crankshaft, and direction
e
(D
2
,
D
4
, D
6
), which is at a right angle to the
crankshaft.
a
: 10.0 mm (0.39 in) from the cylinder head top
surface
b
: 5.0 mm (0.20 in) above the exhaust port
upper edge
c
: 5.0 mm (0.20 in) below the scavenging port
lower edge
6F650350
6F650360
6F650355
6F650356
POWR
5-27 6H95G11
Power unit
Cylinder bore diameter (D
1
— D
6
):
78.000 — 78.020mm
(3.0709 — 3.0716 in)
Cylinder gauge
1
:
90890-06759
6H95G11_05 04.8.20 11:05 Page 28