Avtodizel ???-238??, Руководство по эксплуатации

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Fig. 12. Piston:
1 – piston; 2 – pin circlip; 3 – pis-
ton pin; 4 – expander; 5 – oil ring; 6
– second compression ring; 7 – top
compression ring
For engines
ЯМЗ
-238
БЕ
and
ЯМЗ
-238
ДЕ
can be used:
1 The piston 238
НБ
-1004015-
Б
4 with 4 grooves for piston
rings (three for compression rings and one for oil ring). The
grooves for top compression ring are made in niresist insert
with the purpose of increase wearlessness. The combustion
chamber is displaced on 5 mm, the lateral surface with hol-
low and has the excluder. The height from the piston pin
axis to piston top surface is increased up to 100 mm. The
piston pin boring diameter is reduced up to 50 mm.
2 The piston 238
НБ
-1004015 is similar to previous one, but it
has not the niresist insert for top compression ring. The
combustion chamber is displaced on 5 mm, without the
ex-
cluder. That piston in unit with the liner is supplied as spare
parts. The numbers of the kits are 238
НБ
-1004008 and
238
НБ
-1004005-A3