Parsun F40 EFI, Maintenance Manual

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3.
Measure the clearance of piston ring end face with a clearance gauge; If it does not
meet the specified value, replace it.
End face clearance (during installation): Top ring 0.15
～
0.30 mm
Second ring 0.30
～
0.50 mm
Oil ring 0.20
～
0.70 mm
4.
Install the piston ring on the piston, and measure the clearance between the piston ring
and the piston ring groove with a clearance gauge; If it does not meet the specified
value, replace it.
Specified clearance: Top ring 0.02
～
0.06 mm
Second ring is 0.02
～
0.06 mm
Oil ring 0.04
～
0.18 mm
Inner diameter of connecting rod small end
Measure the inside diameter of the small end. If it does not meet the specified value,
replace it.
Inner diameter of small end: 15.985
～
15.998 mm
Connecting rod large end backlash
Measure the big-end backlash.
If it does not meet the specified value,
replace the connecting rod or crankshaft or both.
Large end backlash: 0.05
～
0.22 mm
Check connecting rod bolts
1. Check the thread diameter of the connecting rod bolt at the position shown in the
figure.
2.
Calculate the diameter difference of two threads; If it does not meet the specified value,
replace it.
Thread diameter difference of connecting rod bolt: 0
～
0.1 mm
Crankshaft
1. Measure crankshaft main journal diameter, crank pin diameter and crank pin width. If
they do not meet the specified value, replace the crankshaft.
Diameter of
crankshaft
journal
42.984~43.000 mm
Crank pin
diameter
32.984~33.000 mm
Crank pin width 21.000~21.070mm
2. Check the crankshaft runout; If it exceeds the specified value, replace it.
a