San Juan 23 as a power cruiser

Discussion in 'Boat Design' started by willy13, Jul 13, 2022.

  1. willy13
    Joined: Jan 2022
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    Location: Canandaigua NY

    willy13 Junior Member

    I found a cheap, needs love, San Juan 23 that has enough interior space that meet our needs to hang out in the Florida Keys for a week or so. I have not bought it yet. I read that when converting a sailboat to a motor cruiser the heavy ballast under water can make the boat rock sharply. So reducing ballast is important. This boat has a short keel with swinging center board from the looks of it. Is most of the weight in the fixed short keel? Could I just remove the center board and leave the keel since it's short?

    I am guessing a 10hp motor will push the boat to 6 mph with the engine being in an efficient RPM range, agree? What kind of MPG should I expect? The boat will be loaded pretty heavy. Only 2 people, but lots of water and stuff.

    Thanks,
    William
     

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  2. kapnD
    Joined: Jan 2003
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    kapnD Senior Member

    The keys are HOT, and this boat has essentially no ventilation.
    There’s a reason why all the Caribbean boats have large shady tops.
    6 hp is more than adequate for this small, light boat.
    Why not sail?
     
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  3. bajansailor
    Joined: Oct 2007
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    bajansailor Marine Surveyor

    Here is some more info on the San Juan 23 -
    SailboatData.com - SAN JUAN 23 Sailboat https://sailboatdata.com/sailboat/san-juan-23

    The GA below is from this link.

    San Juan 23 GA.jpg

    How cheap is 'cheap'?
    Is the boat already in Florida, or will you have to trail it there from New York?
    Re your photo, the boat seems to have a mast - does she have sails as well?
    If she does, then I am sure it would be more fun to sail her around the Keys, rather than just motoring without the mast and the centreboard.
    Or are you simply not too keen on sailing?
    If so, have you come across any dedicated small powerboats for sale within the same price bracket as this San Juan?
     
  4. willy13
    Joined: Jan 2022
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    Location: Canandaigua NY

    willy13 Junior Member

    At this point my wife and I simply do not feel like we want to learn how to sail. Maybe we will change are minds, but if it gets the fuel economy that the Macgregor 26x gets, or claimed by owners, (9 mpg at 5 to 6 mph), then I feel like we would just rather motor. It does have a mast and sails, but since I am not a sailor I don't know if everything else is there and working.

    I did buy it last night for $950. It is near where I live and will be picking it up tonight. From now till the winter we will be making it our own inside and comfortable for us. Then trailering it to Florida this winter. I feel like the boat was free and the trailer is worth the $950.

    Lots of sailors recommend just getting powerboats. Most are too heavy, too wide to trailer, are built for big motors, and have small cabins. It seems straight forward to me, if you want to go slow and spend nights in it, convert a sailboat to a motor cruiser. Do these sailors just not like to see a sailboat get converted, is it sacrilegious? It should have better fuel economy than sticking a small outboard on a old powerboat anyway, correct?

    I will do research on if anyone has done the conversion yet.
     
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  5. kapnD
    Joined: Jan 2003
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    kapnD Senior Member

    I would urge you to try it out under sail. Motoring it is not sacrelige, but you should appreciate that the designer focused his efforts on creating this craft to sail effectively. Sailing a small boat is quite simple, and who knows, you might enjoy it immensely! A small outboard will move it easily, but Is the transom strong enough to carry an outboard?
    Is there safe storage space for gasoline aboard?
    The mast and keel work together to keep the boats motion comfortable, so altering either can have consequences.
     
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  6. Tops
    Joined: Aug 2021
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    Location: Minnesota

    Tops Senior Member

    Hello William,
    Congrats on the boat, I bought something similar a few years ago that I have been repairing and motoring and sailing (in that order of decreasing magnitude) since. Mine was a basket case but I did it anyways. I would also encourage keeping it a 'sailor with aux motor' for now. There is a thrill in backing out under power, turning around, and stopping the motor and hoisting the sail to get underway. There is also joy in a good-running motor and working nav lights to get you back to the dock in the dark after the wind dies down for the day. I knew a retired couple that sailed and camped all around the country with a San Juan 23. The Skipper (he) told great stories and the Admiral (she) would bake and bring along cookies for everyone at the Messabouts (gathering of homemade and other boats) they attended. A 50w solar panel, charge controller, battery, and fan work well for me to keep 12VDC power in the boat and added ventilation while working in the cabin.
     
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  7. Flotation
    Joined: Jan 2020
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    Flotation Senior Member

    In addition to the other arguments already posed here i'd like to add that learning how to sail and knowing how to safely navigate a boat under power share a 92% overlap in things you'll need to know. The bit of extra knowledge needed to use your sails more or less effectively pales in comparison to the rest of the things you have to know about boating in general. That bit of extra knowledge has the potential to make stay on the boat immensely satisfying though.
     
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  8. bajansailor
    Joined: Oct 2007
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    bajansailor Marine Surveyor

  9. boatgm2
    Joined: Nov 2011
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    Location: guam

    boatgm2 Junior Member

    Shamrock Electric Sailboat Conversion Part 2 - Sea Trials with 72V Lithium Battery Bank
     
  10. willy13
    Joined: Jan 2022
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    Location: Canandaigua NY

    willy13 Junior Member

    I think there would be less controversy if I asked if I should undergo gender reassignment surgery, lol. Kidding aside, some good information, I will hold off cutting the keel, but the snappy roll from not having the mast is still a question.

    I'll post a picture, but the bottom of the hull seems to be flatter than some other sailboats. So hopefully it doesn't roll more than a typical power boat. I looked hard and long for power boats that had big cabins. They were all wider than 8.5 ft and heavy. I got tired of looking so had to make a move....

    I liked the O'Day 20 that was converted to a proa that someone shared over there. Amazing that it gets 14 miles per gallon at 5 knots. But I am still planning to build an aluminum displacement cruising catamaran, so not sure I want to go down the proa road with this boat. This boat is to confirm that we want to live on a boat for a couple weeks at a time.
     
  11. bajansailor
    Joined: Oct 2007
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    bajansailor Marine Surveyor

    I think you should just leave the ballast as it is and see how the boat behaves without a mast - it is only a very shallow keel, and you will be adding more weight anyway higher up re your cruising outfit and stores.
    And you could as well leave the centreboard there as well, if it is in reasonable condition, especially so the pivot bolt. It might be useful for helping to reduce rolling if you are at anchor with a cross swell.

    Re your aluminium displacement catamaran, can you share your thoughts about it on here please, or perhaps on a new thread if you don't want to hijack your San Juan thread? How far have you progressed with this so far? Do you have a stock design in mind?
     
    Last edited: Jul 18, 2022
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  12. willy13
    Joined: Jan 2022
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    willy13 Junior Member

    I started a couple of threads on this forum asking specific questions I had about my aluminum cat project, but the plans have changed since my last post. I will start a more dedicated thread when my plans are more defined as it is still in the brain storming stage. The San Juan will get us to the keys sooner and cheaper.

    I posted on the Fakebook book site in hopes that someone did the actual conversion on a San Juan 23. I prefer actual forums, I find it odd how fakebook organizes threads. Probably just me.
     
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  13. bajansailor
    Joined: Oct 2007
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    bajansailor Marine Surveyor

    Ah ok, I remember now your original thread about the ally cat - I should have looked up your previous postings.
    Displacement Hull Power Catermaran https://www.boatdesign.net/threads/displacement-hull-power-catermaran.66751/

    Rather than starting a new thread (as your plans and thoughts re this cat have since changed), it could be useful to simply carry on with the old thread, and this would show very well how you are going around your own 'design spiral' in the quest to design your ally power cat.
     
  14. willy13
    Joined: Jan 2022
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    willy13 Junior Member

    Here is a picture of the round hull. It is certainly round, but maybe not as round as a larger sailboat? Regarding rolling when not sailing maybe I got lucky. I need to get the outboard I already had running before finding out. It's an old 7.5 hp Evinrude my grandfather used for fishing on a small aluminum boat. It will be fun hearing it again. On the same lake he fished on but pushing an big old sailboat.
     

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  15. Tops
    Joined: Aug 2021
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    Location: Minnesota

    Tops Senior Member

    I have the same make/hp engine on my 21-footer, no troubles moving the boat. Mine has a shaft extension. Only issue is I can bump the prop on the rudder if I am not careful, I may need to either link them together or move the motor mount out. I need to patent a keel guide mechanism for my trailer like yours. Could I trouble you to show a picture from the back please?
     
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