Westerbeke 6.5 MCG Service Manual page 34

CRANKSHAFT, BEARING AND OIL SEAL
R - 0.059/N [1.5MM]
MEASURE THE CRANKSHAFT OIL CLEARANCE
The crankshaft oil measured by using a plastic gauge
as follows:
1. The oil and grease and other foreign matters fonn
the
crankshaft journal and bearing inner surface.
2.
Install the crankshaft.
3.
Cut
the plastic gauge to the same length as the width of
the bearing and place it on the journal in parrallel with its
axis.
4. Gently place the main bearing cap over it and tighten the
bolts to the specified torque.
5. Remove the bolts and gently remove the main bearing
cap. Measure the width of the smashed plastic gauge
(at
its widest section)
by
using the scale printed on the
plastic gauge.
SCALE
PLASTIGAUGf·
INSPECTING THE CRANKSHAFT REAR OIL SEAL
1. Inspect the oil clearance lip for wear or damage. Check
the rubber portion for deterioration and hardening.
Replace the seal if at
all
suspect.
2. Check the oil case for cracks and damage. If here is
damage, replace the case.
32
CRANKSHAFT BEARINGS SPECIFICATIONS
Upper and Lower .
When the bearings are to be replaced, select the correct ones
and install them in positions according to the identification
marks stamped on the crankshaft and the top surface of the
cylinder block.
CRANKSHAFT JOURNAL DIAMETER
Identification Marks
1
2
3
Journal Diameter
1.5746-1.5748 in
~39.994-
40.0DOmmJ
1.5743-1.5746 in 39.988- 39.994mm
1.5741 ·1.5743 in 39.982 • 39.988mm
N0.2 ARM
CRANKSHAFT BEARING THICKN~SS
CAMSHAFT JOURNAL
Identification Colors
brown-
blue
yellow
green
Bearing Thickness
0.0783-0.0784 in (1.988 -1.991mm!
0.0784 • 0.0785 in {1.991 • 1.994mm
0.0785 • 0.07861n 1.994 ·1.997mm
0.0786 • 0.0787 in 1.997 • 2.000mm
0.0787 - 0.0789 in {2.000 - 2.003mm
CYLINDER BLOCK
CYLINDER BLOcK BEARING DIAMETER
Identification MarkS
0
I
][
Bearing Inner Diameter
·1.7323 -1.7325 in
~44.000
• 44.006mm}
1.7325-1.7328 in 44.006- 44.012mm
1.7328 -1.7330 in 44.012- 44.018mm
BEARING
IDENTIFICATION
MARKS
CRANKSHAFT BEARING SELECTION CHART
Crankshaft Journal
Crankshaft Bearing Cylinder Block Bearing
ldentlfJCatlon Marks Identification Marks
Identification Marks
1 brown 0
I
blue
][
2
0
blue
I.
yellow
:u:
3 blue 0
yellow
I
green
][