5) Remove cap and using a scale (2) on gaging plastic envelope,
measure gaging plastic (1) width at the widest point (clearance).
If clearance exceeds its limit, use a new standard size bearing
and remeasure clearance.
6) If clearance can not be brought to within its limit even by using
a new standard size bearing, regrind crankpin to undersize and
use 0.25 mm undersize bearing.
ASSEMBLY
NOTE:
Two sizes of piston are available as standard size spare part
so as to ensure proper piston-to-cylinder clearance. When
installing a standard size piston, make sure to match piston
with cylinder as follows.
a) Each piston has stamped number 1 or 2 as shown. It represents
outer diameter of piston.
b) There are also stamped numbers of 1 and 2 on the cylinder
block as shown. The first number represents inner diameter of
No.1 cylinder, the second number of No.2 cylinder, the third
number of No.3 cylinder and the fourth number of No.4 cylinder.
Flywheel
side
1 or 2
Crank
pulley
side
No.1 Cylinder
No.2 Cylinder
No.3 Cylinder
No.4 Cylinder
6A1-56
ENGINE MECHANICAL
SH410
Item
Standard
Limit
Bearing
0.020 – 0.050 mm
0.080 mm
clearance
(0.0008 – 0.0019 in.)
(0.0031 in.)