Yaroslavl ???-236 Maintenance Manual page 34

Assembly of the compression and oil-control rings at the piston one should perform
with the help of the special device for rings unlocking.
Compression rings are installed with mark "Upper side" directed to the piston top.
2.8.19 At the cover of the connecting rod to mark the order number of the cylinder. Kits of
the connecting rods with the pistons one should install at the engine in accordance with cylinder
numbers marked at the connecting rod covers and it is necessary to check previously
correspondence of the reference numbers of the cover and connecting rod. Installing the piston
block displacement of the tube in the piston should face the engine axis. Before tightening of the
bolts at the cap fasteners thread and butt end of the bolt head should be lubricated with diesel oil,
bolts should be screwed for 2-3 threads by hand.
Connecting-rod bolts should be screwed in two steps:
I step – 98 N*m ( 10kfg·m );
II step – 196-216 N*m ( 20-22 kfg·m );
Gripping should be begun from the long bolt.
Total clearance between the butts of the connecting-rod big end and connecting rod journal
(axial play of the connecting rod) should be within the limits 0.3-0.94 mm. Measurement should be
taken between the butts of the connecting rods. After the installation of the connecting rods with
pistons crankshaft should rotate by hand with the help of lever with the arm 0.55 m evenly without
sticking.
2.8.20 During the installation of the camshaft one should provide protection of the bearing
plugs from the damages, previously lubricated their bearing journal with diesel oil. Font gears and
the driver of high-pressure fuel pump should be installed according to the marks. Side clearance in
the gears engagement should be within the limits 0.09-0.22 mm (measurement should be taken in
three points).
2.8.21 During the installation of the oil pump one should provide the side clearance in the
gears engagement of the crankshaft with the idle gear of the oil pump within the limits 0.25-0.37
mm. It is allowed, if necessary, to install no more than three shim washers (236-1011380) between
the pump body and the cap of the base bush bearing of the crankshaft.
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