Westerbeke 5.0KW BCG-60Hz Service Manual page 30

PISTONS AND CONNECTING RODS
Installing the Connecting Rod Bearing Caps
Since the connecting rod cap bolts and nuts are torqued
using the plastic area tightening method, the bolts should be
examined before reuse.
If
the bolt threads are "necked
down". the bolt should be replaced.
Necking can be checked by running a nut with fingers to the
full length of the bolt threads. If the nut does not run
smoothly, the bolt should be replaced.
Before installation of each nut, apply clean engine oil to the
thread portion and bearing surface of the nut.
Install each nut to the bolt and tighten it with your fingers.
Then tighten the nuts alternately to install the cap properly.
Tighten the nuts to the proper torque.
CAP NUT TIGHTENING TORQUE 11+90· turn (15Nm +90· turn)
A
CAUTION:
If the cylinder head has been installed
before installing the connecting rod cap nut, remove
the spark plugs.
Make a paint mark on the head of each nul Make a paint
mark on the bolt end at the position 90° to 100° from the
paint mark made on the nut in the direction of the tightening
nul
Give a 90° to 100° tum to the nut and make sure that the
paint mark on the nut and that on the bolt are in alignment.
If the nut is turned less than 90°, proper fastening
perfonnance may not be expected. When tightening the nut,
rum it sufficiently.
If the nut is overtightend (exceeding 100°), loosen-the nut
completely and then retighten it by repeating the tightening
procedure.
Engines & Generators
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