Fuel System

May 12, 2017

 

The two fuel tanks are located in the hulls where they are an integral part of the boat structure.   Each tank holds approximately 3200 liters of diesel fuel, for a total of 6400 liters.

 


To refuel each tank has a big fill line that goes to the side of the house.  To vent the tanks and enable fast refueling a big vent line goes to the same location on the side of the house.

Each tank has four lines that that terminate with a flange and a 1/2" shut-off valve that accomplish the following functions:

One sump line (also called a stripper tube) that goes to the bottom of the tank and is used to pump out manually any water or dirt that has deposited on the bottom of the tank. With tanks that are part of the hull it is not a good idea to put a plug at the bottom of the tank since it would be located higher up in the tank and would be more difficult to service than a sump line.

One fuel level line to measure with a dipstick the amount of fuel left in the tank.

One fuel line out that goes to about 100 mm above the bottom of the tank that draws out the fuel.  When emptying the tank from the fuel out line about 25 to 30 liters of fuel remain on the bottom of the tank,

One return line that returns any unused fuel from the engine, crossfeed fuel or polished fuel.

The fuel out line.

The fuel is filtered by a double Separ filter/water separator located in the engine room.  A vacuum meter monitors the condition of the filter and if necessary a valve lets you switch filter without shutting down the engine.

An electric fuel pump after the filters can be used to pressurize the lines going to the engine or generator.  This pump is also used to transfer fuel from one tank to the other or to return the fuel to the fuel tank it was drawn from, thus cleaning (polishing) the fuel.  For more on polishing the fuel see the technical article on fuel.

All the fuel lines and hardware are 1/2" stainless steel or appropriate, RINA approved fuel hoses.

A flow meter on the fuel out after the filters and one on the fuel return line monitors the fuel used.

 A set of valves and auxiliary in and outlets on the fuel lines above the fuel tanks let you draw and return the fuel from a small portable auxiliary tank that is used to calibrate the flow meters. 

Be aware that the fuel outlets in the engine rooms are below the fuel level in the tanks when the tanks are more than one third full.  

 

Procedures

Before changing the position of any fuel valve make sure that you know what you are doing and that you are closing or opening the right valve.  Failure to do so may over pressurize the system and cause a catastrofical failure.

In Harbor and Navigation

Each engine draws fuel from its own tank.
Keep all valves in a ready position.  You may never know when you have to start the engines or the generator.

The fuel out and return valves on top of the tanks are open.
The sump drain and fuel level lines are shut.

The crossfeed valves on top of the tanks that go to the tanks on the other side must be shut.

The crossfeed or fuel polish valves in the engine rooms must be shut.
The fuel pump bypass valves must be open.

The engines or generator fuel out and return valves in the engine rooms must be open, unless the generator or other users have been shut down.

 

Boat Inactive or Hauled Out

The fuel out and return valves on top of the tanks are shut.   The sump drain and fuel level lines are shut.

The crossfeed valves on top of the tanks that go to the tanks on the other side must be shut.  The crossfeed or fuel polish valves in the engine rooms must be shut.

The engines or generator fuel out and return valves in the engine rooms must be shut.

 

Measuring Fuel Quantity

Currently the way to measure the fuel quantity in each tank is to measure the distance between underside of the top of the tank and the fuel surface.

The fuel quantity is calculated by multiplying the tank area width with the length of the tank, which is 2485 mm.
The distance between the bottom of the tank to the top of the tank is 1312 mm.

Distance from
Fuel to Top
Distance from
Fuel to Top
Tank area Fuel Quantity Fuel Quantity
mm inches dm ^2 liters %
     
Full tank Full tank 130.4 3241 100
100 3.94 119.1 2959 91.3
200 7.87 107.8 2680 82.7
300 11.81 96.6 2400 74.1
400 15.75 85.7 2129 65.7
500 19.69 74.6 1853 57.2
600 23.62 63.8 1583 48.8
700 27.56 53.0 1317 40.6
800 31.50 42.3 1051 32.4
900 35.43 31.8 790 24.4
1000 39.37 21.7 539 16.6

 

Refueling

Before refueling estimate the quantity of fuel left in each tank by measuring the fuel level with the fuel dipstick or the Maretron fuel meters and then calculate the approximate amount required.  This is important especially when filling the tanks at high speed to avoid any fuel spillage.

  Add the proper amount of diesel bio killer additive to each tank.

Proceed cautiously when the tanks are nearly full in order to stop before fuel overflows from the vent line.

Take into account when refueling that the generator draws fuel only from starboard tank.

 

Priming the Fuel System

If for some reason air enters into the fuel system or the fuel system has to be filled with fuel proceed as follows.

The fuel out and return valves on top of the tanks are open.

Open the crossfeed valve in the engine room.
Shut the fuel pump bypass valve.

Turn on the electric fuel pump until the fuel flows back into the fuel tank.

 

Sump Check

After refueling let the fuel settle for a few hours, then proceed as follows to check if the fuel contains water or dirt.

Connect a small hand pump to the sump drain line and pump out a small quantity of fuel into a tall glass receptacle.  Let the fuel settle and check for water at the bottom of the receptacle. If there are any traces of water or other foreign matters, pump out until only clean fuel appears.  Dispose of any contaminated fuel properly.

If necessary, proceed with the fuel polishing procedure, explained below.

 

Cross Feed

If for any reason one engine runs more than the other it may be necessary to transfer fuel from one side to the other to maintain a proper trim of the boat.

The fuel out valves on top of the tanks are open.

On the receiving tank side open the crossfeed valve on top of the tank .  Make sure that the fuel return valve on top of the tank is open.

On the side of the tank that supplies the fuel open the crossfeed valve and close the fuel return valve on top of the tank.

In the engine room of the tank that supplies the fuel open the crossfeed valve and shut the fuel pump bypass valve. Turn on the electric fuel pump.
You may transfer fuel even when the engines or generator are running.

Be aware that transferring fuel from one tank to the other is a slow operation, since the electric fuel pump is small and the fuel has to pass through the fuel filter on the side that supplies the fuel.  Frequently check the fuel level of the receiving tank.  There are no automatic shutoffs when transferring fuel and if not careful you may end up spilling fuel.

After a large fuel transfer check the status of the fuel filter on the side that supplied the fuel.  If necessary change it.

 

Fuel Polish

If the fuel appears to be contaminated with dirt or water you can "polish" the fuel, that is clean it by filtering it and return it to the same tank it came from.

 In April 2017 sludge was found in the fuel filter of the port tank, indicating algae and bacterial growth in the fuel.  This problem has become more frequent due to the presence of bio-diesel due to the European Union legislation permitting a mixture of biological based diesel fuel and mineral based diesel fuel .  Since it is not feasible to empty a tank and clean it the best course of action is to polish the fuel for a long time (minimum 12 hours) and then add a recommended dose of diesel bio killer.  It is then recommended to add the recommended dose of bio killer whenever refueling.

The fuel out and return valves on top of the tanks are open.

Make sure that the crossfeed valves on top of the tanks are closed.

In the engine room of the side you want to polish the fuel shut the fuel pump bypass valve and open the crossfeed valve.
Turn on the electric fuel pump.

After polishing the fuel check the status of the fuel filter and if necessary change it.

Be aware that polishing fuel is a slow operation, since the electric fuel pump is small and the fuel has to pass through the fuel filter.  Don't worry about the pump.  It can be run for days without damage.

 

Engine Room Fire

If possible, immediately close all the fuel valves on top of the fuel tank on the side where there is the fire. 

 

Tank Inspection

To perform the operation described below both tanks must be less than half full.

Each tank has three big inspection plates that can easily be removed in order to give access to the three sections of the tank.

To empty a tank first transfer all the fuel following the cross feed procedure described above.  Then pump out the 25 to 30 liters left in the tank as if performing a sump check.

After having emptied the tank you can proceed to unbolt the inspection plates.

An empty fuel tank can be very dangerous.  Get expert help to clean the tank and remove all the remaining vapors.  

After having done whatever had to be done to the inside of the tank bolt down the inspection plates.  As a sealant you can use the polyurethane sealant 5200, after having carefully greased both sides that come into contact with the sealant with a thin coat of grease.  If you don't do this carefully you will not be able to open the plates in the future.

 

Maintenance

Check the fuel filters and fuel sight glass daily for impurities.

Every few months or after having purchased doubtful fuel pump proceed do a sump check, as explained above. 

 

Log

2015

May 27

Refuel.  Port 1320 l      Stbd 1578 l    Total 2898 l        in Genova harbour 1.39 E/l cash
Maretron   63%   65%
May 30 Maretron   56%   58% in Porto Azzurro Elba
June 5 Maretron   54%   56% in Porto Azzurro Elba
  Engine  Port 1421.69 hrs  Stbd 1320.53
June 12 Maretron   51%  53%  in Porto Ferraio
July 2 Maretron   50%  46% in Porto Ferraio
  Engine Port 1437.52 hrs  Stbd 1336.33 hrs in Porto Ferraio
July 11 Maretron  %?  41%
  Engine Port 1451.85 hrs  Stbd 1350.62 hrs in Genova
July 16 Engine Port 1454.0 hrs  Stbd 1352 hrs in Genova

 

Refuel.  Port 220 l      Stbd 500 l    Total 720 l        in Genova harbour 1.39 E/l cash
Maretron   51%   56%
July  17 Maretron   51%   56% in Porto Venere
August 22 Maretron   ?%  37% in Porto Azzurro
  Stick  67 - 13 = 54 cm about 1600 l   75 - 13 = 62 cm about 1590 l  
  Engine Port 1478.20 hrs  Stbd 1376.86 hrs

2016

February

Changed the Fleetguard fuel filters on both engines
  Added the focus tubes to the fuel meter levels.  Now the instrument displays low levels.
Port stick:  65 cm from fuel surface to underside of top of tank about 1400 l.  Maretron 32%  
  Stbd stick:  75 cm from fuel surface to underside of top of tank about 1180 l.  Maretron 27%
May 14 Refueled at ERG station in Genova, added about 1800 liters (E 1100 stbd E 900 port)
  Engine Port 1503.97 hrs  Stbd 1402.43 hrs
  Maretron   56%   54%
May 20 Maretron   50%   48%  Nizza Villefranche
May 25 Maretron   50%   46%  St. Tropez
July 4 Refueled at ERG station in Genova, added 1555 liters (l 650 port E 905 stbd) E 2100
  Maretron   63%   68% 
July 10 Maretron   57%   61%  Marina di Campo
July 11 Maretron   57%   60%  Marina di Campo
July 29 Maretron   56%   56%  Porto Ferraio
July 31 Maretron   50%   50%  Calvi, Corsica
August 4 Maretron   40%   39%  Erbalunga, Corsica
August 4 Maretron   37%   37%  Marina di Campo
August 8 Maretron   36%   35%  Porto Ferraio
August 15 Maretron   35%   32%  Porto Azzurro
August 16 Maretron   30%   27%  Porto Venere
August 16 Maretron   29%   26%  Genova in the marina
   

2017

February

Maretron  27%   24% in Genova
April 11 Engine Port 1627.74 hrs  Stbd 1526.08 hrs
  Changed the forward Separ fuel filters and the Fleetguard fuel filters of both engines
Discovered biological growth in port fuel filter sight glass.
May 8 Polished the fuel of both tanks for about 12 hrs, emptied the fuel filters and replaced all the four filters.
  Maretron   27%   875 l  24%  777 l  Genova in the marina
  Added 2x 125 ml of Green Star diesel bio killer to each tank and then polished the fuel for 12 hrs.
  Changing the port side aft sight glass the O-ring got damaged and had to be replaced.  Vacuum escaped.

 

Equipment

Fuel Tanks

The two fuel tanks are located in the hulls and are an integral part of the boat structure. On top of each fuel tank there are three inspection covers, used to inspect and give access to the tanks.

Each tank holds approximatively 3200 liters of diesel fuel, for a total of 6400 liters.

On top of the tank are welded  6 pipes, from inboard to outboard (right to left in the picture):

Sump drain line.  18 mm inside diameter pipe going to the lowest part of the tank, for pumping out any water or dirt that may collect in the tank.

Fuel level line.  18 mm inside diameter pipe going to the inside of the tank, for measuring with a dipstick the fuel level.

Fuel vent pipe.  60 mm diameter pipe, the top is welded to the fuel intake compartment on the side of the house.

Fuel fill pipe.  50 mm diameter pipe, the top is welded to the fuel intake compartment on the side of the house.

Fuel line.  18mm inside diameter pipe going to about 100 mm above the bottom of the tank, so as to leave behind any small amounts of water or dirt .

Return line.  18 mm inside diameter pipe going to the top of the tank.

Crossfeed line.  18 mm diameter pipe going to the top of the tank.

Each tank has been tested with water pressurized to 0.2 bar.

 

Fuel Valves and Piping

All the four aluminum pipes welded to the top of the tanks terminate with an aluminum flange.  A stainless steel flange with a stainless steel valve bolted to the aluminum flange completes the piping to the tanks.  A Teflon seal assures a leak free union between the two flanges.

The ball valves have locks that have to be moved before being able to turn the handle, therefore avoiding any accidental operation.

All the piping to the fuel filters and for the crossfeed are 1/2" stainless pipes.

1/2"  SS ball valves
8 Teflon seals

 

Fuel Hoses

Fuel hoses are permitted, even in the engine room, provided that they have been approved as fuel hoses.  The best material are fire-retardant, marine, reinforced neoprene hoses with a burst pressure of 250 psi. 

Fuel connections in the system are made  with the large ISO-7840 certified fuel hoses to avoid transmitting vibrations to the hulls.
Small ISO-7840 certified fuel hoses are used to connect the engines to the fuel system.

Vetus FUHOSE fuel hose  ID 8mm, OD 16 mm

Vetus FUHOSE fuel hose  ID 13mm, OD 22 mm

Vetus Italia srl
Via Palandri, 41
I-50050 Limite sull'Arno (FI)
Phone: +39 0571 57122
Fax: +39 0571 578143
e-mail:
info@vetusitalia.it
www.vetusitalia.it

 

Fuel Filters

Two double Separ 2000 diesel filter/water separator, one for each engine.

A valve lets you switch filter without shutting down the engine.  The sight glass on the bottom of the filters lets you check the quality (color) of the fuel and if there is any water in the fuel, which can then be drained with the valve on the bottom of the filter.

When draining fuel from the filters you must use a container to collect the contaminate fuel, which must then be disposed of properly!

All the filters have to be replaced whenever needed or once a year.

2

Separ 2000 fuel filters Type SWK 2000/10 UKD

Willibrord Loesing
Essener Strasse 108
D-455529 Hattingen
Phone: +49 02324 946 00
Fax: +49 02324 40842
e-mail: info@loesing-filter.de
www.5w40.de

The following manual provided by the manufacturer is also part of this section:

Separ  2000 fuel filter

In addition to the Separ 2000 fuel filters each engine also has a Fleetguard fuel filter attached to the body of the engine.

2

Fleetguard - Cummins fuel filters FF 5285

 

Fuel Pumps

Marco, 24 V, 1/2"gear diesel fuel pump.

These two pumps are mainly used to pressurize the fuel system.  Since these pumps are also used to transfer fuel from one tank to the other or to polish the fuel they have be be able to run for an long amount of time.  Usually fuel pumps are not continuous duty and have to be turned off after a short time of running.  To avoid this problem the used pumps are nominally of 24 V.  Running them at 12 V avoids any overheating problem and lets you run the pump for an inderfinite time.  This procedure has been discussed and approved with the pump manufacturer.

The port pump, due to its location, has to turn in the opposite direction than the one indicated by the arrow on the pump body.  This reversal is achieved by inverting the power supply.  Also this procedure has been discusses and approved by the pump manufacturer.

2

Marco UP6 fuel pumps, 24V Model 164 06013

Marco spa
Via Mameli, 28
I-25014 Castenedolo (BS)
Phone: +39 030 21341
Fax: +39 030 2134300
e-mail:
info@marco.it
www.marco.it

Fuel Flow Meter

To monitor the fuel flow two series K high flow FloScan meters are used.  Each flow meter has a forward and a return sensor assembly, located in the engine room.  

The flow meters are connected to the auxiliary engine key on circuit and will turn on automatically when turning the ignition key of the corresponding engine.  Make sure that the Key on breakers in the engine room are turned on.

To reset the port and starboard totalizers go to the underside of the top instrument panel, below and inbetween the two FloScan instruments, where there are two holes.  Insert a screwdriver or similar tool into the hole until you can feel that it hits a pushbutton.  To reset keep the pushbutton pressed for a few seconds.

The port side flow meter (NMEA) shows besides liters per hour also how many liters per nautical mile are burned by the port engine.  To achieve this the instrument must be connected to the GPS for speed and range information.  If the GPS signal is absent, you can switch to show the regular fuel flow in liters per hour.

A cable with 4 wires comes from each engine room to the instrument panel.

Yellow
Green
White
Brown

goes to Ground
goes to white, forward flow sensor
goes to brown, return flow sensor
goes to 12V, key on

For the RPM meters each instrument is connected directly to the corresponding engine RPM meter (gray wire)on the bridge panel.  The calibration is set to 161.

 

 

2

FloScan flow meters  P/N 980M0 - 3CB - 2K www.floscan.com

The flow sensors are labeled as Feed or Return flow.  The serial numbers must stay with the meter they came with and must be installed in the fuel system as labeled.

Port:
Starboard:

Forward serial #10241
Forward serial # 10244
 
Return serial # 10321 
Return serial # 10370
Instrument serial # 21180 NMEA
Instrument serial # 21181 PULSE


The following manual provided by the manufacturer is also part of this section:

FloScan  Series K Diesel Fuel Flow Monitoring System

 

Auxiliary Fuel Tank

The small auxiliary fuel tank can be connected to the auxiliary in and out valves of the fuel system ro measure the actual fuel consumption.  This precise, actual fuel consumption is used to calibrate the fuel flow meters and measure actual fuel consumption of one engine.

The auxiliary tank is made of a piece of aluminum tube with an ID of 1900 mm.

The plastic pipe that is used as a sight glass has an ID of 25 mm.  Therefore each mm of fuel height corresponds to 28.83 ml of fuel.

 

Literature

Captn Wil's Diesel Polishing System Wil Anderson September 13, 2000
 

 

2017-05-12
cat_11_e fuel.htm