Shibaura SG280E, Workshop Manual

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26
6. Connecting rod metal
1) Inspect the metal, and replace it if it shows
signs of peeling, melting, notching, or poor
contact.
2) Use a plasti-gauge to measure the oil
clearance between the crank pin and the
metal.
Before measuring, clean away all dirt and
oil.
Cut the plasti-gauge to a length equal to the
width of the metal, and place it on the crank
pin parallel to the crankshaft while also
avoiding the oil channel.
Tighten the connecting rod cap to the rated
torque, and then confirm that removal is
complete.
Tightening torque
48 to 54N
⋅⋅⋅⋅
m (5.0 to 5.5kgf
⋅
m)
*
Measure
without turning the crankshaft.
Use a piston heater to heat the piston to 100 degrees
centigrade. Then, assemble by aligning the head of
the piston on the combustion chamber side with the
mark at part A on the connecting rod as shown in the
figure on the right.
Pay careful attention to the numerical mark on part A
of the connecting rod during assembly.
Orient the mark on the connecting surface of the
piston ring so that it faces upward, and install it on
the piston.
Install the expander jointed part for the oil ring on
the opposite side of the ring connecting opening.
[Assemble with the connecting opening of the
piston ring turned 120 degrees to avoid the piston
pin direction and the direction perpendicular to the
pin.]
Clearance between crank pin and connecting rod metal
[oil clearance] (mm)
Assembly standard Usage limit
0.035 to 0.085 0.2 or more
Set the plasti-gauge. Measure the oil clearance.
Assembling the pistons, connecting rods, and piston rings
Fig.2-5-22
Fig.2-5-20 Fig.2-5-21
Fig.2-5-23
A