Yanmar 2TNV70 Service Manual page 141

Cylinder Block
7. Reinstall the oil ring expander
(Figure 6-88, (4)). Install the oil ring
(Figure 6-88, (3)) with the end gap at 180° from
the expander end gap.
8. Reinstall the second compression ring
(Figure 6-88, (2)). This ring is identified by its
dark color and tapered face profile.
9. Reinstall the top compression ring
(Figure 6-88, (1)). This ring is identified by its
silver color and barrel-shaped face profile.
IMPORTANT
The oil ring expander (Figure 6-88, (4)) end
gap must be located 180° from the oil ring
(Figure 6-88, (3)) end gap.
(4)
Figure 6-88
10. Stagger the piston ring end gaps at 120°
intervals (Figure 6-89, (1, 2, and 3)). Do not
position the top piston ring end gap in line with
the wrist pin.
TNV IDI Service Manual
1 – Top Compression Ring End Gap
(1)
2 – Second Compression Ring End Gap
3 – Oil Ring End Gap
(2)
Installation of Crankshaft
(3) 1. If removed, reinstall the key and timing gear on
crankshaft.
2. Install new bearing inserts (Figure 6-90, (1))
and thrust bearing (Figure 6-90, (2)) in the
cylinder block and main bearing caps. Be sure
0001722B
the oil holes in the upper bearing shells align
with the oil ports in the cylinder block. Apply a
liberal coat of clean engine oil to the bearings
and crankshaft journals.
(1)
(2)
Figure 6-89
ENGINE
(3)
6-55