Cylinders; Oversizes; Cylinder Liners; Bearing Metals - Mitsubishi 4DQ50 Service Manual

Top and oil rings are chromiur:n.plated in sliding surfaces, while the other, namely,
2nd. are tapered, install these taper rings with marks "UP" on cut ends up.
To oil ring is attached a spring type expander to provide high and uniform contact
pressure. The ends of spring are butted to each other with a short steel wire between
them.
Arrangement of piston ring cut ends is indicated in Fig. 5·9.
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Direction of CAM SHAFT e<"
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(Direction of piston pin)
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COMBUSTION CHAMBER JET
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Fig. 5-9 Arrangement of piston ring cut ends
4 CYLINDERS
4-1 Oversize
In Model 40050 Engine, cylinders, being cast in one body with crankcase, have dry
liners.
When they have got worn more than O.2mm in bore or cut deeply in lines, machine
them to a suitable oversize. Oversize pistons and piston rings are available in three sizes:
+0.25, +0.50 and +0.15.
4-2 Cylinder liners
If oversize parts are not available or when they have got worn over the limit of use
(+1.20mm), change cylinder sleeve. For detaiis, ask your dealer or a service shop.
5 BEARING METALS
5-1 General cautions
Handle metals on main bearings and connecting rods always with good care not to
scratch or otherwise damage their bearing surfaces. In assembling them, clean bearing
surfaces and coat them with oil; then clamp them down, making sure that they are free
from any strain.
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