Viking VSC 61 FY User manual

Table of Contents
•Preliminaries
•Introduction
•Vessel Operations
•Fuel System
•Propulsion System
•Electrical System
•Electrical Safety
•Bilge Pumps
•Heating / Cooling System
•Fire Emergency
•Corrosion Protection
•Subsystems
•Water System
•Sanitation System
•Vessel Care
•Addenda
•Service Numbers Directory
VSC
61 FY
Owner’s Manual

v1.0
Owner’s Manual
Fuel System - 22 Viking Sport Cruiser 61FY
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The Publisher’s Statements on
page i of this Owner’s Manual apply
to this chapter. Please read before
proceeding.
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Fuel System
This chapter outlines fuel system components and how
they integrate.
Major Topics:
Fuel system overview (and drawing) 23
Separ fuel filters 24
Backflushing 24
Fuel filters, Separ service 25
Refueling the vessel 26
TABLE OF CONTENTS

v1.0
23 - Fuel System
Viking Sport Cruiser 61FY
Owner’s Manual
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Fuel System: Overview
Tanks and fuel lines
Fuel capacity is 790 gal U.S., held in four welded alumi-
num tanks in the engine room connected as port and star-
board pairs. Each pair comprises a wing tank and a con-
nected fwd bulkhead tank. Each pair (port and starboard)
acts as a single tank because of a normally open balance
pipe connection between them. There is no connection,
however, between port and starboard sides. Tanks have in-
ternal baffles to add strength and reduce sloshing of fuel
in a seaway.
Each side is filled separately (into the wing tank). And each
side supplies one engine only. The starboard tank also sup-
plies the generator.
Pumps on the engines draw fuel from the tanks. More fuel
is pumped to the engines than they can burn (to avoid
fuel starvation). Unburned fuel returns to its tank of origin
via the fuel return lines. The return fuel is warmed by its
passage through the engine and thus it carries heat back
to the main tanks which gradually get warmer and warmer.
This residual heat in the tanks, as it cools, can result in
condensation on the tank walls which, combined with infil-
trating oxygen from the vents, can promote bacterial growth.
Use antibacterial additives, and keep tanks well filled. Moni-
tor filters for water, dirt, and bacterial debris.
A vent from each tank allows air to escape or enter. If the
tank is overfilled fuel will spill out the vent, particularly
with boat motion, so do not overfill the tanks (see the
section in this chapter on Refueling The Vessel).
Control valves
Remote fuel shut-offs, A, are installed on the top of
both tanks. They are operated from the deck service
locker, starboard side (shown in inset). The valves are
for safety – they enable the fuel supply to be shut off
for both engines and the generator.
If you close any of these valves you must ensure that
the engines or generator cannot be started until the
valve is opened again.
Tank top valves (shown open)
Generator Engine
Remote fuel shut-offs
B– Port engine
C– Starboard engine
D– Generator
These are in the starboard
cockpit service locker and
operate the tank top valves.
Typical
Leaking fuel is a fire hazard. Inspect
system regularly and correct any
leakage problems before operating
the vessel.
B C
A
D
Fuel supply, port
Fuel supply, starboard
Fuel returns
Balance pipe, port
Balance pipe, starboard

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Owner’s Manual
Fuel System - 24 Viking Sport Cruiser 61FY
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Separ Fuel Filters
Fuel must be filtered to remove water droplets, rust, al-
gae, asphaltines, varnishes and algae – all prevalent in
diesel fuel today.
How they work
Fuel is sucked out of the tanks, into Separ 2000 fuel fil-
ters, a pair for each engine. Usually only one filter in a pair
is selected, the other being spare. The raw fuel spins rap-
idly inside the bowl and the centrifugal action separates
out large particles of dirt and water droplets (30 microns
and larger) which are thrown into the centre of the bowl,
and collect at the bottom. These you will see and can
drain out.
The fuel continues to spin and enters the top filter ele-
ment, which is usually 30 microns.
Sensors G trigger an alarm if water in the bowl rises to the
sensor level. It must be drained as soon as possible. At
high injector pressures water can turn to steam and damage
the injectors.
If the helm water-in-fuel alarm (icon inset) goes off you must
take action. Most commonly, you will use selection lever L
to close the contaminated filter and swith over to the spare.
However, the contamination must be dealt with
before reactivating the unit – usually by
“backflushing” the affected filter (see next sec-
tion and your Separ manual.)
Be very careful if backflushing a
Separ while underway – you are
close to a spinning shaft and any
fuel that might spill is a fire hazard.
Bleed Screw
Clean Fuel Out
Raw Fuel In
Swirling action
separates out
dirt and water
droplets which
settle in the
bowl.
Filter Element
→
←
←
Water and dirt
contaminated
fuel can be
drained into a
fuel-safe con-
tainer.
Backflushing
If you suspect dirt and water are blocking the filter me-
dia and reducing fuel flow to the engines, the Separs
can be partially cleared by backflushing. This can be
while underway if absolutely necessary.
Move the selection lever fully to the spare filter (i.e.,
close the filter to be backflushed). Open bleed screw
E at the top of the closed filter. Air will enter, and fuel
will flow back through the filter. Assisted by gravity,
contaminants will fall to the bottom of the glass bowl
for draining.
To drain, push IN and TURN drain valve F; catch fuel in
a suitable container until flow is clear. Close drain valve.
Close bleed valve E. DO NOT OVER-TIGHTEN. Check
for leaks.
Separ 2000 filter pair - selection lever
Lever Lselects which filter unit to use. In this photo
the position of the lever shows the filter at left is in
use. The bleed screw Eis for backflushing, and valve F
for draining the bowl. Gis excessive water sensor.
→
→
F
G
E
L
IN USE SPARE

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25 - Fuel System
Viking Sport Cruiser 61FY
Owner’s Manual
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Fuel Filters, Separ Service
Filter restriction affecting fuel flow is indicated by surging at
high revs, black smoke, or visible contaminants in the col-
lection bowl. The restricted filter must be taken off line and
serviced. You can likely run on the spare (assuming it’s clean)
until reaching harbor, but the pairing arrangement allows
either filter element to be changed while underway if neces-
sary. The procedure is described briefly here – but Read the
Separ manual !
Changing a Separ filter element
Turn off engine. Close fuel valve. Backflush the filter by
opening bleed screw E at the top of the filter, Push in and
turn drain valve F. Drain contents into a suitable container.
Close drain valve F. Close bleed screw E.
Loosen lid screws and remove lid. Carefully lift out the
spring frame B. Watch that the springs do not come out of
their housings. Remove filter element A, and replace with
a new one, 30 micron. Place spring frame Bon top of filter
element A. Fill filter with clean fuel. Check that gasket Cis
correctly seated. Align cover plate D, and gasket C. Screw
lid down tightly.
Open system fuel valve. Use priming pump to ensure sys-
tem is full of fuel. Start engine and check for leaks.
Secondary fuel filters
After leaving the Separ filter, fuel is pumped by the pri-
mary fuel pump into a pair of MAN secondary fuel filters
(on the top of the engine beside the oil change pump).
These are spin-on disposables – turn clockwise to remove.
They must be replaced according to schedule: every 200
hours, or yearly. The fuel pre-cleaner, which is part of the
fuel primer pump, requires the same service. Clogged
filters make engines difficult to start and reduce perform-
ance considerably.
If you run out of fuel . . .
After refueling, you must use the priming pump beside
the secondary filters to pressurize and vent the system.
It may also be necessary to bleed air from the secondary
fuel filters as well as the Separ. See your MAN instruction
book.
Bleeding the fuel system (of air)
If either the Separ or the secondary fine fuel filter elements
are replaced, the fuel priming pump must be used to pres-
surize the fuel system. Pages 27-29 of the MAN instruction
book show the procedure in detail. Note that the fuel primer
pump is also a fuel pre-cleaner.
→
←
←
→
File photos taken at a boat show
Optional vacuum gauge (inset)
The Separ cover plate can been modified to install a
vacuum gauge. This gives a visual warning of filter
clogging. Available at Separ Dealers.
Generator fuel filter
The generator has its own fuel filter,
Separ 2000/5M in the lazarette. The
filter element should be replaced
every 200 hours when servicing the
engine, depending on the hours it
has run.
Secondary fuel filters
Have a MAN diesel mechanic service these filters.
secondary
fine fuel
filters
bleed screw
B
C
D
E
F
A
C

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Fuel System - 26 Viking Sport Cruiser 61FY
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Refueling the Vessel
After Fuelling:– Clean up any fuel
spilled on the deck and dispose
of rags ashore. Reinstall fuel
deck plates and tighten down.
Open the windows and deck
hatches. Check for diesel odor
in cabins. Inspect engine room
tanks for any fuel leakage. Switch
on ignition (but don’t start) to run
engine room blowers for at least
5 minutes. As soon as possible
after that start the engines and
move away from the fuel dock
area.
Water-in-fuel alarm
Warning light and alarm Cindi-
cates excessive water in the
Separ fuel bowl. This must be
drained off as soon as possible.
Fuel Deck Plate
Importance of keeping tanks topped up
Fuel tanks should be kept topped up. In a heavy sea
with low fuel the motion of the vessel could allow the
fuel pickup to draw in air instead of fuel.
Tanks left half full of diesel oil are subject to condensa-
tion which promotes rapid growth of algae. When the
fuel tanks are filled, the algae die and foul the fuel in
the tank. Result: dirty fuel filters that must be cleaned.
Antibacterial additives such as Biobor JF or Technol
403 will help
with this prob-
lem, but keep-
ing the fuel
tanks topped
up will reduce
algae growth.
Fuel quality:– Cut price fuel can contain water and other
contaminants. Refuel only at a reputable dealer; it saves
money in the long run. It is best to refuel late in the day to
minimize fuel tank condensation.
Antibacterial additives:– In Florida, especially, fuel tanks
become contaminated with microorganisms. Algae coats
the outside of the filter element causing filters to easily
plug up, particularly the primary fuel filter. If the engines
are starved of fuel because of clogged filters engine power
is reduced and the piston rings may be damaged. Be sure
to always install a 30 micron element in the Separ Fuel
Filter – anything smaller will clog up quickly, and there is
no gain in it.
Antibacterial additives such as Biobor JF must be used to
kill these contaminates. There are many brands on the
market – use them liberally and all the time.
Procedure:– Refueling has to be from both sides. The fill
caps are under deck plates Aat the side deck steps and
are clearly marked DIESEL. Fill both tanks to the same level.
During fueling the vessel must be securely tied up. All
windows, doors and hatches closed. All electrical equip-
ment switched off. Have a fire extinguisher handy.
All crew and passengers should be off the vessel. One
person aboard to monitor the refueling. NO SMOKING.
The fuel gauges Bare a very reliable magnetic type gauge,
but no fuel gauge is 100% accurate. With experience, you
will get to know about how much fuel you need and how
accurate your own gauges are.
Allow for fuel expansion. DO NOT OVERFILL. Unless you
require maximum range, when the gauge indicates full,
stop there. If fuel comes out of the overboard vent stop at
once.
Environmental laws prohibit fuel oil
contamination of sea and lake
water. Be responsible in disposing
of discarded fuel. Always inspect
for leaks when in the engine room.
B
A
C
C
B
C
B