Westerbeke W-46 - Page 28

INSPECTION/REPAIR
c. Check the contact pattern of
the connecting-rod bearing
on the cr ankpin by placing
the large end into its
operating position with the
crankshaft laid out on a
bench, and by applying a
paste of red lead or
Prussian blue to visualize
the contact. Be sure to
tighten the capscrews to
the specified torque,
S.Skg-m (39.8lb-ft). The
conta.ct should occur over
75% of the entire surface;
if not, replace the bearing.
(NOTE: The above job of checking the contact pattern may be
eliminated where the crankpin is ground to the specified
tolerance and the bearing has been replaced. This is because
a replacement bearing is precis ion-finished to ensure the
specified extent of contact).
d. Check each bearing shell for
crush. Shells found to be
loose in the bore or have an
excessive crush must be
replaced. A crush of up to
0. 04mm (. 0016in.), which
will yield to a load of
350kg (772lb.), is pre-
scribed. As in the case of
the main bearing shells,
some crush is needed for
securing a proper fit,
without which the bearing
might roll or jump in place,
resulting in localized over-
loading and consequent flak-
ing, burning or fatigue
failure.
Check to be sure that the
crush disappears to allow
the bearing cap to rna te the
large end positively when
the capscrews are tightened
to S.Skg-m (39.8 lb-ft).
26
Crush:O to 0.04 mm
(0.0016 in.)
Connecting rod bearing crush