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evenly all around.
It is best not to drill the foundation for the
foundation bolts until the approximate alignment has been accurately
determined.
Never attempt a final alignment with the boat on land.
should be in the water and have had an opportunity to assume
water form.
I t is best to do the alignment wi th the fuel
tanks about half full and all the usual equipment on board
the
main
mast
has
been
stepped
and
final
rigging
accomplished.
The boat
its final
and water
and after
has
been
Take
plenty of
time
in
making
this
alignment
and do not
be
satisfied with anything less than perfect results.
The alignment is correct when the shaft
can be slipped backward and forward into the
counterbore very easily and when
a
feeler
gauge indicates that the flanges come exactly
together at all points.
The two halves of
the
propeller
coupling
should
be
parallel
within
0.001
inches
per.inch
diameter
of
coupling (A).
In making the final check for alignment,
the engine half coupling should be held in
one position and the alignment with the pro-
peller
coupling
tested
with
the
propeller
coupling in each of four posi tions, rotated
90· between each position.
This test will also check whether the pro-
peller
half coupling
is
in exact
alignment on its
shaft.
Then,
keeping the propeller coupling in one position, the alignment should
be checked rotating the engine half coupling to full position each 90·
from the next one.
The engine alignment should be rechecked after the boat has been
in service for one to three weeks and, if necessary, the alignment
remade.
It will usually be found that the engine is no longer in
alignment.
This is not because the work was improperly done at first
but because the boat has taken some time to take its final shape, and
the
engine
bed
and
engine
stringers
have
probably
absorbed
some
moisture.· It may even be necessary to re-align at a further period.
The coupling should always be opened up and the bolts removed whe-
never the boat is hauled out or moved from the land to the water, and
during storage in a cradle.
The flexibility of the boat often puts a
very severe strain on the shaft or the coupling or both when it is
being moved.
In some cases the shaft has actually been bent by these
strains.
This does not apply to small boats that are hauled out of
the water when not in use, unless they are dry for a considerable
time.
EXHAUST SYSTEM
Exhaust line
installations vary considerably and each must be
designed for the particular installation.
The prime requirements are
to provide an outlet line with a minimum of restrictions and arranged
so that sea water, rain water and condensation cannot get back into
the cylinders of the engine.
The
sea water
supply line feeding
raw cooling water
into the
system must be routed so as to prevent a siphoning of raw water
through this line into the exhaust system filling the muffler and
engine cylinders.
This line should be routed at least 12 inches above
6
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