Shibaura ST330, Workshop Manual

Page: 43 / 250

38
6) Connecting rod metal
Inspection
(1) Check the metal and if peeling, melting, uneven wear,
improper contact or other damage is noticed, replace the
metal.
(2) Measure the oil clearance of the crank pin and metal using
plasti-gauge.
➀ Remove oil dust or other foreign matter stuck to the
metal and crank pin.
➁ Cut plasti-gauge to the length same as the metal width
and place it on the crank pin in parallel with the
crankshaft avoiding the oil hole.
➂ Install the connecting rod metal and connecting rod
cap and tighten with the specified tightening torque.
Tightening torque
49.0 – 53.9 N · m
｛
5.0 – 5.5 kgf
·
m
｝
NOTE: Never turn the connecting rod at this time.
➃
Remove the connecting rod cap and measure the
plasti-gauge width with the scale printed on the gauge
envelope.
NOTE: Measure the widest part of the plasti-gauge.
(3) If the oil clearance exceeds the service limit according to
the result of the measurement, replace the metal.
Reassembly (piston and connecting rod)
(1) Heat the piston to about 100°C with a piston heater or the
like and install it aligning the SHIBAURA mark in the
piston and match mark at (A) of the connecting rod.
(2) Care should be taken to the figure match mark at (A) of
the connecting rod.
(3) Install the piston ring to the piston facing the stamp at the
end surface of the ring end gap upward.
(4) When the connecting rod or piston and piston pin are
replaced, weight variation among cylinders with the rod,
piston and piston ring installed should be within 10 g.
Clearance between crank pin and connecting rod metal
(oil clearance) (mm)
Standard assembling value Service limit
0.035 – 0.083 0.2
Set a plasti-gauge
126Y
Measure the oil clearance
127Y
Metal size Metal code No.
Crankshaft pin
outside dia. Finishing
dimension ( ∅ )
N843 198517252 51.964
－
51.975
128Y