determining Engine size?

Discussion in 'Diesel Engines' started by wildbill, Feb 21, 2012.

  1. wildbill
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    wildbill Junior Member

    what size engine would be recommended for a 60' power boat with and 18' beam?..... what is good estimate of fuel consumption per hour?
     
  2. WestVanHan
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    WestVanHan Not a Senior Member

    I'd say about 20 hp,and you can look at using around 4l an hour.
     
  3. wildbill
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    wildbill Junior Member

    and that is sufficient horsepower for a 60' boat?
     
  4. Ad Hoc
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    Ad Hoc Naval Architect

    Is it hard chine, round blige?
    What is the max weight of the boat?
     
  5. ldigas
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    ldigas Senior Member

    60 foot boat with a 18 foot beam? If I'm reading those apostrophes correctly ... then that would be 18.3m boat with 5.5m beam.

    Displacement around 25-30 tons, depending on the type of the hull?

    The required power depends on speed, naturally, which is unfortunatelly missing, and the term "power boat" is somewhat vague to me - power as opposed to sail boat, or "power boat" meaning those fast racing boats? In my part of the world it usually means the former.

    In any case, on a cruiser (by no means a racing boat) which I've recently been occupied on, the power required for 7-8 knots was 70kW and for 11 knots it was 350kW. Maybe you could use these as orientation values.
     
  6. wildbill
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    wildbill Junior Member


    yeah thx.... big help there... a lot of variables but that gives me a starting point....

    power boat as in no sail.... not racing .... speed is nice but economy is better since it will be use for commercial fishing .... design is typical SE Asian pom boat with stabilizers... flat bottom


    wow that is a big jump from 7 to 11 knots .... even at the low end if my calculations are correct..... i am looking at 20 liters per hour?
     
  7. Stumble
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    Stumble Senior Member

    It all depends. If you are looking at dragging nets it could be twice that fuel burn for 3kn depending on the size of the trawl, hull shape, power takeoffs for ice boxes, ect. My 60' burns between 2 gallons an hour at 6kn to 20/hr at 15kn. But I also know 60' that burn 100gallons/hr at 37kn. It all depends. There are also highly efficient hulls like my old sailboat 58' that got .9gallons/hr at 8kn.
     
  8. wildbill
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    wildbill Junior Member

    what engine are you running in your cruiser? .... i like that ratio.... nice to have power when you need and efficiency when you dont .....

    this boat will used primarily as a tender ... taxiing small boats to and from the tuna grounds .... storage of ice, fuel, groceries.... delivering fish to market ..... very low tech....
     
  9. daiquiri
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    daiquiri Engineering and Design

    Wildbill, you need to give more info. The required power will depend on you boat's dimensions (LWL, BWL, draught), displacement, hull type and particularities (example: canoe or transom stern, mid-section shape, number of engines, appendages etc.), desired cruise or max speed, typical expected weather conditions and sea states etc. There are various methods for calculation of engine power, which one should be used will depend on the above (and not only) data.
    You could check this thread too: http://www.boatdesign.net/forums/boat-design/calculating-power-displacement-boats-38487.html

    Cheers
     
  10. wildbill
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    wildbill Junior Member


    thanks for the link ..... a plethora of info ..... glad i stumbled upon this msg board...you guys have been most helpful....................wb
     
  11. michael pierzga
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    michael pierzga Senior Member

    Well , hauled at the yard is a 60 ft motorboat. She needs two thousand hp to move along . Dont know how much she drinks...probably so much that you avoid starting the engines.
     
  12. wildbill
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    wildbill Junior Member


    damn..... what is that a high speed tug? .... my calcs are 1 gal of fuel per hour for every 19 hp .... thirsty girl...........
     
  13. michael pierzga
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    michael pierzga Senior Member

    Men with gold chains and dark sunglasses use these vessels to transport bikini clad girls to the beach.
     

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  14. ldigas
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    ldigas Senior Member

    I'm not familiar with those boats. Do you have an image of the boat out of the water or a rough lines plan you could put up?
     

  15. powerabout
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    powerabout Senior Member

    16-92's nice
     
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