Maintenance Manual for J2 Sedan
Mechanical Part of Engine
78
Attention:
■
Be careful to prevent gasket materials from falling into the engine oil or coolant.
Measure planeness of cylinder body in different
directions at six positions using ruler and feeler gauge.
Standard values: below 0.05mm
Limits: below 0.1mm
If the limit is exceeded, replace cylinder body.
⑥
Cylindricality of Cylinder
Measure the cylinder degree at 6 different points per cylinder by using micrometer.
Standard values:
For cylinder bore: 75.0mm
For cylindricality: below 0.07mm
⑦
Diameter of Piston Skirt
Use outside micrometer to check whether the
piston skirt is distorted.
Standard values:74.973mm
⑧
Clearance between Piston and Cylinder Bore
Calculate per the actual measurement of piston skirt and cylinder bore.
(Gap)
＝
(inner diameter of cylinder)
－
(diameter of piston skirt)
Standard value: 0.02-0.04mm
If the calculated value exceeds the limit, replace piston and piston ring assembly.
⑨
Boring Cylinder
a.
The piston with extended size to be used should be determined in accordance with the cylinder
which has the highest bore.
Pistons of the following extended sizes, i.e. 0.25mm, 0.50mm, 0.75mm and 1.00mm, are applicable.
b. Measure the diameter of piston to be used.
After boring cylinder, clearance between piston and cylinder bore must be within standard range. The
Fig.1.1.063
Fig.1.1.064
Feeler
Gau e
Ruler
Dial Indicator
