3、Piston 、Connecting Rod - YANGDONG YD380D Operation & Maintenance Manual

Fig.7 Measu rement o f piston
ring end ga p
1. Thickness feeler(gauge )
The piston connection rod assembly consists of piston, piston ring, piston pin,
retainer ring, connecting rod, connecting rod casing, connecting rod bolt, connecting rod
bushing and connecting rod lining and etc. Mass deviation of the connecting rod
assembly of the piston for the same diesel shall be no more than 3g. ZL109 alloy
aluminum is employed for the piston.
The gaseous ring is made of alloy cast iron. External circle of the first gaseous ring
is coated with porosity chrome, which can reduce abrasion between cylinder sleeve and
piston ring. The second gaseous ring is a taper-face ring, the surface marked TOP faces
the top face. Reversing assembly is not allowed.
Caulking ring is employed for the oil control ring. As its resilience reduces by
abrasion, it still remains a certain of radial resilience, therefore, it extends service life of
the oil control ring.
Please check clearance of the opening before installing the piston. Keep the piston
ring flat. 15-20mm away from top face of the cylinder sleeve. Then measure it gas feeler,
clearance of the opening shall be 0.3-0.4mm. See figure 7 for detail. If with clearance of
the opening is smaller, amend it with a file; if clearance of the opening is larger, change a
new one, In addition, it's necessary to measure the end face clearance between the
piston ring and the piston ring groove with a gap feeler. Clearance for the first gaseous
O P E R AT I O N & M A I N T E N A N C E M A N U A L
3、Piston and connecting Rod
Fig.8 Measurement of side surface gap
of piston ring
2.piston ring 3. Cylinder liner
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