Fuel Distribution System-

Discussion in 'Diesel Engines' started by MikeAune, Feb 5, 2013.

  1. MikeAune
    Joined: Feb 2013
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    Location: Jersey City

    MikeAune Fevik

    I would like to design a new fuel system. Goals are to maximize flexibility and at the same time try to keep things simple. Key difference would be to filter fuel prior to a manifold, then from manifold supplying fuel to BOTH genset and main engine, with the added ability to pump back into take for fuel polishing. Concern is when running just genset or main, could you pull air into the system from the engine that is not running. I could use a check valve, but i would rather not as that could be a point of failure. Any suggestions, ideas, etc would be greatly appreciated.. Thanks!!
     

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  2. FAST FRED
    Joined: Oct 2002
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    Location: Conn in summers , Ortona FL in winter , with big d

    FAST FRED Senior Member

    My concerns are that both the engine and noisemaker will be fighting for fuel sucking against each other in the fuel block.

    Far better to have individual. pickups and filters from the tank for each.

    Different solution would be a day tank , after the filters , that could GRAVITY feed the boat for a reasonable operating time.
     
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  3. MikeAune
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    MikeAune Fevik

    Thanks Fast Fred. I don't think starving one of the engines would be problem as into the manifold is all 1/2" fuel line and the outflows are 1/4" and the manifold is below the tank. I suppose it would be wise to get with may a 1" diameter manifold, fed in the middle to insure equal distribution. Do you see a problem sucking air back into the system from a not running engine? I'm not even sure if that's possible but the concern has been raised. Looking to ask a mechanic on that one as well.
     
  4. michael pierzga
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    michael pierzga Senior Member

    what happens if you must isolate one fuel tank because of contamination ? two main engines and two generators will be pulling on the same fuel supply and filter ? Filter clogs and all power is lost.

    I prefer a dedicated Racor on each consumer and for this filter to be at the engine, after the manifold


    Also since you are setting up a new system think about fuel transfer. A typical scenario is that, for instance , your port tank is contaminated with 20 gallons of water. How will you transfer the top, CLEAN, 300 gallons of fuel from your contaminated port tank into your clean stb tank , at sea, and keep the show on the road.

    This is a typical maneuver so you should prepare. When fuel return lines penatrate the tank to 75 percent depth, they make good transfer intakes and avoid any possiblity of letting air into the fuel intake system

    As far as an additional fuel polishing system, I wouldnt waste the money. Ive operated for many years, worldwide, with only racor filters and proper yearly tank cleanout.
     
  5. MikeAune
    Joined: Feb 2013
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    MikeAune Fevik

    You make good points as well Michael P... Space and maintenance/access considerations is what is driving me towards locating the filters remotely. I agree with everyone that ideally i have a dedicated fuel line and filter to each engine but just hoping to avoid that. I will noodle with a new design that i hope will still work with what i am trying to do and post that... I really appreciate all of your feedback. Oh and as far as an underway transfer that might be beyond the scope of what i wish to accomplish. I'd be happy with a bottom of the tank transfer/polish for now. But that is a solid idea as well. I will think about that with the new design to see if i can make it work.
     
  6. FAST FRED
    Joined: Oct 2002
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    Location: Conn in summers , Ortona FL in winter , with big d

    FAST FRED Senior Member

    and proper yearly tank cleanout.

    Usually ALL the fuel system hassles can be solved with the addition of an access port.

    A better solution is a real self serviceable fuel tank , but that requires
    the tank to be directly below the fuel fill , EZ of a work boat or a new build , hard on an existing yacht.

    The simple but sloppy cheap solution is the clean out opening.

    A Great!!! solution (for the fuel system but not the engineer) is the use of a powered centrifugal fuel filter as done on commercial vessels.

    The units are being made in Yacht size now , but the clean out is still a really messy task.

    Really nice if the system let you filter the fuel as its taken aboard , and again before actual use.
     
  7. michael pierzga
    Joined: Dec 2008
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    michael pierzga Senior Member

    Ive never had a problem with taking on dirty fuel .

    All the crud in the tanks is growth. Ive tried the miracle additives, but now I find it easier and cheaper to pop the top off the tanks, dive in and clean the tank walls and bottom every two years. Not difficult, i love diesel fumes...two tanks are a whole weekends fun

    I generate about 15 lites of MUD every two years.

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  8. FAST FRED
    Joined: Oct 2002
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    Location: Conn in summers , Ortona FL in winter , with big d

    FAST FRED Senior Member

    Practical Sailor tested "bug killers" and suggests that different selections be used as no one kills everything.

    Water is the key , there are no bugs with out an oil water interface.

    They live in the water , eat the oil , and the sludge you see is their waste and dead bodies.

    Stop the water and you will cure the problem , unless the sludge is coming at no extra cost with the fuel.

    BAJA filter during some part of the fill will answer that question.
     
  9. michael pierzga
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    michael pierzga Senior Member

    Water ? to my knowledge Ive never removed a drop of water from my tanks.

    Its possible you mean fuel contact with air ?
     
  10. philSweet
    Joined: May 2008
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    philSweet Senior Member

    Mike, two suggestions-

    1. Show us the original layout for comparison.

    2. Show us all the lift pumps.

    3. <edit> I'll add a third question- What functions do you need to accomplish at the helm, and which are ok to go spelunking in the engine bay to do.

    Is the date on your sketch correct? What's been happening for the last year?
     
  11. philSweet
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    Location: Beaufort, SC and H'ville, NC

    philSweet Senior Member


  12. FAST FRED
    Joined: Oct 2002
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    Location: Conn in summers , Ortona FL in winter , with big d

    FAST FRED Senior Member

    The sole advantage to this big buck item is the ability to switch tanks while seated at the helm , instead of at the manifold below.

    Is that an advantage to your operation?

    Sure violates KISS principals !
     
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