Yanmar 3YM20, Руководство по обслуживанию

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4. Disassembly and reassembly
89
4.3.2 Reassembly
(1) Clean all parts
Clean all parts using by the cloth and diesel oil (or cleaning agent) before reassembly.
NOTE:
1) If the dust remain with the parts, engine may cause the seizing or damage.
2) The cleaning agent removes even carbon adhering to disassembled parts.
(2) Putting the cylinder block upside down
Place a wood block on the floor and put the cylinder block upside down (with the cylinder head mounting
surface facing down).
(3) Inserting the tappets
Coat the inside of the cylinder block tappet holes and the outside circumference of the tappets with
engine oil, and insert the tappets in the cylinder block.
NOTE:
Separate the tappets to make sure that they are reassembled in the same cylinder No. and intake/
exhaust side as they came from.
(4) Mounting the crankshaft
1) The crankshaft and the crankshaft gear are shrink
fitted. If the crankshaft and the crankshaft gear
have been disassembled, they have to be shrink
fitted [heat the crank shaft gear to 180- 200 deg. C
in the hot oil and press fit to the crankshaft].
2) Coat the crank journal part of the cylinder block
and the upper main bearing metal with oil and fit
the upper main bearing metal onto the cylinder
block.
NOTE:
1) Be sure not to confuse the upper and lower main
bearing metals. The upper metal has an oil
groove.
2) When mounting the thrust metal, fit it so that the
surface with the oil groove slit faces outwards,
crankshaft side.
3) Coat the crankpins and the crank journals of the
crankshaft with engine oil and place it on the upper
main bearing metals.
NOTE:
1) Position so that the crankshaft gear is on the
gear case side.
2) Be careful not to let the thrust metal drop.
(Removing main bearing and crankshaft)
Crankshaft
Thrust metal
Main bearing
(Base)
Cylinder block
Main bearing
Main bearing bolt