Yanmar BY Series Service Manual page 125

Cylinder Block and Crankshaft
12/05
(c) Bearing shells are marked with yellow,
green or white paint (Figure 5-117). Select
bearing shells with color that matches the
paint on the crankshaft. NOTICE: Ensure
the bearing inserts and bearing mounting
surfaces are absolutely clean and free of oil.
Ensure all blind threaded holes are clean
and free of oil or other fluid.
Figure 5-117
Figure 5-117
Note: Install thrust bearing insert (edges wrap
around) in position 4 on 4BY2 and
position 6 on 6BY2. Install insert half
having an oil hole in the cylinder block
(Figure 5-118).
Figure 5-118
Figure 5-118
BY Service Manual
2. NOTICE: Install ONLY bearing inserts with
yellow identifying paint in the cylinder block
main bearing bores. Install yellow-painted main
bearing inserts in the cylinder block and main
bearing caps. Apply a generous amount of
clean engine oil to the bearing inserts. Ensure
all oil holes are properly aligned. Do not
lubricate the crankshaft journals at this time.
3. Carefully lower the crankshaft into place. Do not
rotate crankshaft.
4. Check bearing oil clearance before proceeding.
See Measure Oil Clearance on page 5-59.
5. Apply clean engine oil to the crankshaft journals
and main bearing inserts after oil clearance has
been checked. NOTICE: The main bearing
caps are marked and must be installed in their
original positions.
Figure 5-119
6. Install main bearing caps with the insert
alignment tabs on the same side as those in the
cylinder block. Lubricate threads on NEW bolts
with clean engine oil and install. NOTICE:
NEVER reuse main bearing cap bolts. ALWAYS
install new ones.
7. Tighten bearing cap bolts to 22 N·m (16 ft-lb).
8. Loosen bolts of the thrust bearing retaining cap
and tighten finger-tight.
9. Move each end of the crankshaft to center
thrust bearing.
© 2009 Yanmar Marine International
ENGINE
Figure 5-119
5-63