Fuel System - Westerbeke ATOMIC 4 Operation And Maintenance Manual

of restriction to flow offered by
the piping. It is quite common to
find engine operating temperatures
as low as 90
0
F. in these installa-
t ions. We do not recommend this type
system because the usually low oper-
ating temperature is conducive to
valve sticking, sludge formation in
the crankcase, dilution of crank-
case oil with cylinder wall conden-
sation and shortened valve spring
life. We recommend a nominal opera-
tion temperature of 150
0
F. obtained
through the use of a by-pass system
as shown in the piping diagrams of
Fig. 11. Do not attempt to control
temperature by restricting the flow
of water either into the pump or
overboard.
In the by-pass syetem a quantity of
warm water leaving the engine is
diverted back into the pump suction
line to be recirculated through the
engine. By varying the amount of
warm water fed back to the pump the
engine temperature. can be controlled.
Control of water passing through the
by-pass line is accomplished with
either a hand control valve or a
thermostat installed as shown in
the piping diagrams. Opening the
valve wiil divert a larger amount
of warm water back into the engine
and raise its operat ing temperature.
If a thermostat is used it will
automatically divert nearly all of
the warm water leaving the engine
back to the pump for recirculation
when the engine is cold. When en-
gine temperature nears 150
0
F. the
thermostat will react to decrease
the amount of recirculated water
and will divert only enough to
maintain engine temperature at
about 150 0 F.
Generally, the thermostat will give
faster warm up and closer tempera-
ture control over the engine speed
range than will the hand control
valve. The hand control valve should
be adjusted to give adequate tem-
perature at the usual running speed
of the engine. It should not be ne-
cessary to continually re-adjust
the valve.
On installations using the hand
control valve, water should be noted
issuing from the exhaust pipe soon
after the engine is started. A lack
of water indicates the pump has not
primed and the engine should be
stopped until the source of trouble
is found.
On installations using a thermostat,
only a trickle of water and some-
times only steam will issue from
the exhaust unt il the engine reaches
operat ing temperature at ,."hich time
the thermostat will open to dis-
charge more water overboard. The
thermostat is designed to allow a
small quantity of water to pass it
and keep the exhaust pipe cool un-
til the engine reaches operating
temperature.
\~ben
start ing a cold
engine always keep a close watch
on the temperature gauge until it
steadies to a constant value.
8. FUEL SYSTE1f
A marine type gasoline tank should
be used in all installations, con-
structed with internal baffle plates
and a filler pipe which goes
nearl~'
to the bottom of the tank. Should a
fire occur during the filling of
such a tank only that vapor trapped
in the filling tube will burn anc
this can be snuffed out by placing
something over the neck of the tube.
The gasoline outlet from the tank
also enters at the top of the tank
and passes down through the tank to
just a short distance off the bot-
tom. This pipe should be slightly
larger in size than that required
by the fuel pump on the engine.
The tank will also have a vent and
overflow tube coming off the top of
the tank of at least half-inch copper
tube size. This tube should be run
as directly as possible to a suit-
able through-hull fitting, located
in most cases just below the sheer
line of the hull. Overflow gasoline
and tank vapors will thereby be
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