/.-",
SERVICE BULLETIN
V3
DATE:
5/6/74
BULLETIN
NUMBER:
69
MODEL:
SUBJECT:
All
marine
generators
and
marine
engines
Exhaust
system
failures
When
engine sea water
is
fed into
an
exhaust
system
so
that the full
stream
strikes
a surface, erosion
may
cause premature
failures.
Proper design of
either
a water jacketed or
~
water injected
{lIwet)1I
exhaust
system
to prevent
this
problem
requires that the sea water
inlet
be
positioned
so
that
the entering stream of sea water
does
not
strike
a surface
directly.
Also, the velocity of the entering sea
water stream should
be
as
low
as
possible
which
is
achieved
by
having
inlet
fittings
as
big in diameter
as
possible.
In
addition to the
above
design considerations,
it
is
usually
advan-
tageous to divide the sea water
flow
at
the point of entry to the
exhaust
system
so
that
only a portion of
it
enters the exhaust system.
The
remainder
is
normally piped directly over the side.
The
proper
proportion of the sea water
flow
to
pass
through the exhaust
system
can
only
be
determined
by
trial
and
error.
The
goal
is
to prevent
excessive exhaust temperatures with the
least
amount
of sea water.
PIN:
19149
J. H. WESTERBEKE CORP.
AVON
'NDU.TR'AI.
,.AR",
AVON,
iliA
•••
02322·
'8f71
588-7700
CA.I..:
Mi
••
TCOR,.,
AVON·
T.I..1C:
.2-4444