GB 42 or 49 re-powered

Discussion in 'Powerboats' started by Brian@BNE, Feb 13, 2012.

  1. Brian@BNE
    Joined: Jan 2010
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    Brian@BNE Senior Member

    I've been taking a good look at some Grand Banks 42. I like the layout, and am happy enough at displacement speeds. Efficiency isn't great - after all its basically a planing hull, built heavy. Typically 35000 lbs lightship.

    Searches showed what seems a bit of an anomaly. GB 49's, older ones, often listed for similar prices. So the thought occurs - why not get a GB 49 for the extra space, standing height engine room and a bit more hull speed. But instead of feeding the 2 x Cat 3208's at 375 HP that they typically have change the power. Either re-power or rig up a chain drive/clutch system to run just one of the monster engines but turn both props, and then cruise at 10 kn at low fuel consumption. The 49's lightship are 60000 lb.

    Am I missing something?
     
  2. keysdisease
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    keysdisease Senior Member

  3. WestVanHan
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    WestVanHan Not a Senior Member

    I guess you could do chains but it seems a bother.Why not just take one prop off...and then change back when you feel?

    I think you would be quite surpised at the mpg at low speeds..even my 21 ton, 1280 hp twin engines running at 7 knots its a bit over 9 lph.

    But get those 3208 Cats checked...seriously checked.

    In trucks they were poor engines,IIRC they have only 2 rings,so lots of blowby and sludge.
    In boats they seem to do better.Also if not loaded properly-they are very succeptible to the usual problems associated.

    The good news is if they are shot, Cummins 6bt or 4BT are dirt cheap and last forever.

    But first of all,realistically figure how many miles/hours you will put on vs. gph vs. cost to change and you may find it will take you 20 to 150 years to pay the new engines off.
     
  4. Brian@BNE
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    Brian@BNE Senior Member

  5. Stumble
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    Stumble Senior Member

    Brian,

    In line with Wests suggestion of taking off a prop, you might also consider putting a feathering prop on the boat. While normally reserved for sailboats, if you are going to run one engine at a time, this would allow you to switch back and forth, and have both engines if you ever needed them for something.
     
  6. Brian@BNE
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    Brian@BNE Senior Member

    Good comments WestVan
    If I buy a GB 42 I will struggle to get enough range to get home, even with some fuel bladders. California to Hawaii is a bit over 2000 nm, then to Samoa is a little further. After that its just island hopping and easy.... If I ship West Coast to Brisbane its in the order of $50k for cradle & shipping. Plus 15% import cost on that freight.

    Ideally I would ship to American Samoa, or some other US territory in the west Pacific. There must be some kind of semi-regular supply runs to these places
     
  7. Brian@BNE
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    Brian@BNE Senior Member

    This is also worth considering. But props are 24" or 28" diameter, so feathering versions will not be inexpensive. If I do end up with 2 x 200+ HP engines, preferably Cummins, then 2 x CPP would be an option. Not inexpensive either, but a good set-up and be very likely better than re-powering. The problem is, once I cross the Pacific the normal usage wouldn't justify the changeover. The journey itself has to give a lot of the payback. I'm trying to test various options, just have this horrible feeling that the checkbook pain of freight could end up being the way to go.
     
  8. Stumble
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    Stumble Senior Member

    Brian,

    I can tell you that often the cost to ship is much lower than the cost to take it over on its own hull. This is the way most mega-yachts move around the world. Some of the transport craft even have full ship yards to do dry dock work during the transit.
     
  9. Brian@BNE
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    Brian@BNE Senior Member

    In my head I know you are right. I'd love to do the trip, but its not without its risks either. It probably only makes sense in a sailboat, and take best part of a year to do it to enjoy places en route. Seems the Pacific Puddle Jump is a fun way to do some of it.
     
  10. sabahcat
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    sabahcat Senior Member

    How about something more fuel efficient?

     
  11. WestVanHan
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    WestVanHan Not a Senior Member

    Try Dockwise- float on and float off.

    There's yacht path,DYT, and seven star that I know of.
     
  12. keysdisease
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    keysdisease Senior Member

    Those Yacht transport ships make regular trips to Australia and New Zealand, and you can stay aboard your vessel enroute.

    http://www.yacht-transport.com/homepage.html

    Ther are other yacht transport companies, but these guys use the floating drydock style vessel exclusively, other's are usually deck transports.

    Steve

     
  13. Brian@BNE
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    Brian@BNE Senior Member

    I read their story a while back. Seems OK. Not that keen on a project like theirs. Could be fun when time comes to sell, and sooner or later it does.
     
  14. Brian@BNE
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    Brian@BNE Senior Member

    Thanks folks, when it gets to the point of making an offer I'll contact Dockwise et al. Staying on board for the trip could be pleasant enough too.
     

  15. Tad
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    Tad Boat Designer

    According to some recent information, if you are flexible about timing and location of pickup/dropoff and can build a shipping cradle, Sevenstar can be "exceedingly affordable".
     
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