Westerbeke W-46 - Page 33

INSPECTION/REPAIR
Install the main bearings in
the crankcase, without the
crankshaft, securing each
bearing cap by tightening the
bolts to 8.5 kg-m (61.5 lb-ft)
and measure the diameter from
two positions, (A) and (B), as
indicated in the illustration.
Measure the journal with a
micrometer. From these
readings, compute the radial
clearance~
Specifications Unit: mm (in.)
Item
Standard
Repair
limit
Fit of main
o.m -o.089
0.2
bearings on
{0.0012- 0.0035) (0.008)
journals
Check each main-bearing shell
for crush. Shells that are
loose in the bore or have an
excessive crush must be
replaced. A crush of up to
0. 04mm (0. 0016in.) ;- which will
yield a load of SOOkg
(1103lb), is recommended.
Positions for measurinq main bearing
Main bearing crush
Crush:
0-0.04 mm
Camshaft
1.
Check the camshaft end play as outlined for
Where the end play exceeds the repair limit,
plate.
Specifications
Unit: mm
(in.)
Item
Nominal
Standard
Repair
value
limit
Camshaft end
5.0
0.05-0.112
0.3
play
(0.197)
(0.00197-
{0.012)
0.00441)
the timing gears.
replace the thrust
2. Inspect the camshaft journals for abnormal wear and damage; the
camshaft must be replaced if any of the three journals is found in
disrepair.
3. Using a micrometer, measure each cam of the camshaft to read Dl
(cam height) and D2 (diameter), then compute the difference bet-
ween Dl and 02. If this difference is less than the service
limit, replace the camshaft.
Engines & Generators
31