Yamato 302, Manual, Page: 10 / 30

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III DISASSEMBLY, INSpECTION AND REASSEMBLY
III - 1 pOWER UNIT
A. Disassembly
1. Remove magneto assembly (see magneto section).
2. It is not necessary to remove fuel tank. However, for the beginner, it will be easier
to work without it.
3. Remove carburettor.
4. Remove intake manifold assembly.
5. Remove reed valve assembly, exhaust flange, cylinder head.
6. Remove power unit by removing six 8 mm nuts using 12 mm box wrench or socket.
7. Separate power unit from lower unit.
8. Remove six 10 mm nuts using 14 mm box wrench to remove cylinder block.
CAUTION: Do not pry with screwdriver or other sharp tool.
9. Remove piston pin clips.
10. Remove piston pin.
11. Remove piston.
12. Remove three 6mm bolts holding lower bearing case assembly (P-18). It is not
necessary to remove tail flange assembly except when replacing oil seal.
13. Remove flywheel and key.
14. Remove four 6 mm bolts holding upper bearing case assembly (P-7).
15. Split crankcase by removing 8 nuts and 2 socket head bolts using 12 mm socket.
16. Split crankcase assembly by tapping with soft hammer. CAUTION: Do not pry with
screwdriver or other sharp tool.
17. Remove crankshaft.
18. Inspect lower bearing assembly without removing from crankshaft. If bearing is
defective, use special tool, Puller-bearing case lower, part # 102-809-0080.
CAUTION: Remove clip (P-24) prior to removing lower bearing assembly.
19. Remove clip (P-17) which holds split sleeve, centre bearing (P-15). CAUTION:
Slight discolouration of center bearing is not detrimental to the life of this bearing.
20. Clean all parts in solvent. Scrape-off carbon and gasket residue.