Main engine primary fuel filters are in the engine room,
starboard forward corner. Arrow points to valve.
(Left) A sight gauge. (Right) The fuel manifold.
4L4: Fuel Filters
The
primary
fuel filters get larger impurities out
of the fuel before it reaches the engine’s fuel pump.
There are a pair of these primary filters for each main
engine The filter in use from each pair is selected by a
valve (arrow) on the front of each filter unit.
There is another filter in the engine room for the
generator just inboard of that unit.
The
secondary
fuel filter is on the engine itself
just before the injection pump system. It is a very fine
filter, and is the final protection to be sure the engine’s
fuel is absolutely clean.
If an engine stops, it is likely a filter is clogged (unless, of course, you’ve run out of fuel!)
Follow engine manual instructions carefully, and remember you may have to prime the engine
to re-start it. See the engine manual for this procedure.
4L5: Fuel Management/Tank Valves
In the forward port corner of the engine
room there is a fuel manifold consisting of a set
of valves for the fuel supply to each main engine
and the generator, and another set for the fuel
return from these engines back to the ship's
tanks. (See “Fuel Manifold” next page).
There are sight gauges on the end of each
tank that let you see the level in each. As the fuel
level in a pair of tanks gets lower, you can switch
the valves so that the return and supply sides
connect to another tank.
Unless you want to change the balance of
fuel between the tanks, be sure to switch both the
supply and return sides of the fuel lines to the
manifolds i.e., if you are "getting fuel from the
forward tanks, "return it to the forward tanks"!
Failure to have the same tanks
both supplying and returning fuel
risks spilling fuel as, after a while,
the tanks getting the "returned"
fuel overflow!
There are also seldom-used valves on each tank itself allowing a tank with
contaminated fuel to be isolated from the others.
Note: The Lazarette Tanks, though detailed in this manual, are not to
be used! The Port Lazarette Tank is empty and the Starboard
Lazarette Tank is full for trim purposes and should be left as is!
Section 4L: Fuel System 4.33
