Generic XOR 50 ccm, Руководство по обслуживанию

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ENGINE COMPONENTS INSPECTION AND SERVICING
BEARINGS
Clear bears with solvent and lubricate
with engine oil before inspecting.
Turn the inner ring and check to see that
the inner rieng turns smoothly. If it does
not turn lightly, quietly and smoothly, or if
noise is heard, the bearing is defective
and must be replaced with a new one.
OIL SEAL
Damage to the lip of the oil seal may result in leakage of the fuel-air mixture or oil.
Inspect for damage and be sure to replace the damaged seal if found.
CRANKSHAFT
CRANKSHAFT RUNOUT
Support crankshaft by“V” block, with the dial gauge
rigged to read the runout as shown.
Service limit
：
0.05mm(0.002in)
Excessive crankshaft runout is often responsible for
abnormal engine vibration. Such vibration shortens
engine life.
Condition of big end bearing
Turn the crankshaft with the connecting rod to feel the
smoothness of rotary motion in the big end. Move the
rod up and down while holding the crankshaft rigidly to
be sure that there is no rattle in the big end.
Wear on the big end of the connecting rod can be
estimated by checking the movement of the small end
of the rod. The method can also check the extent of
wear on the parts of the connecting rod ‘s big end. If
wear exceeds the limit, replace connecting rod, crank
pin and crank pin bearing.
Service limit
：
3.0mm(0.12in)