Weifang 495 - Maintenance of Crankshaft and Connecting Rod Mechanism

These lines -are used together with the pointer -marked on the
flywheel housing to check and adjust the injection advance angle.
Each aluminium alloy piston is fitted with tl:ree compression
rings and J-wo oil rings. The top compression ring is chrome plated
to improve its wear resistance under high temperature. The cham-
fe~ on the outer periphery of the oil ring, used to improve its oil
scraping capability. Should be upward in mounting the oil rings on
the piston ,never put them upside down.
The piston pin is of the full- floating type, when the certain
working temp'erature of the piston is reached, the piston pin may
rotate in its bore to even its wear. But at the cold state, it fits in
the bore with interference fit, therefore the piston should be pre-
heated before the pin remounted or dismounted from it .
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The connecting rod big end is split ~long the 45° inclined dia-
metrical line., After machinning both t11e connecting rod, shanks
and caps are 4t,~lmarked in couples with numbers and it is forbidden
to mix them IIp. _
i\ bronze/bushing used in the smal~ end of the connecting rod.
The oil hole on the bushing should be aligned with the oil hole on
the smallen(l of the connecting rod so as to facilitate lubrica~ing
the bushing and the pis ton pin.
2). Maintenance of Crankshaft and Connecting rod Mechanism
(1) Dismantling and Inspecting Crankshaft-Connecting Rod
Mechanism
A. The following points should be noted when dismantling
and inspecting the crankshaft -connecting rod mechanism.
a.The dismantlement and inspection should be carried out in a
clean room.
b. Check all fixing and locking parts for their tightness. Note
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