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Duffy Electric boats....?

Discussion in 'Tenders & Dinghies' started by Norseman, Sep 18, 2013.

  1. Ted Graham

    Ted Graham New Member

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    Now that the batteries are working, I'd like to address the leaking packing gland. This is an ElectraCraft LSR 18 which seems very similar to the Duffy boats most of you have. What size packing should I use?

    The propeller shaft is 1" and when I measured the packing nut and divided the difference by 2 I ended up buying 1/8" packing but it feels way too loose. I'm thinking I need 1/4" packing but would appreciate comments.
  2. Fishtigua

    Fishtigua Senior Member

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    Hi Ted, have a close look at the stuffing box, a mobile phone with the torch on helps, there could be a stamp in the metal telling you what size to use. It could be 3/16th or 5/16th also.
  3. Rob Houston

    Rob Houston New Member

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    Congratulations on getting it done, Ted. That's certainly a good price for AGM's. I hope that 85Ah is sufficient to meet your needs. Unfortunately, that capacity is too low for my boating.

    Good luck, and have fun on the water!
  4. Ted Graham

    Ted Graham New Member

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    Regarding the packing material, ElectraCraft wrote (I don't know if this applies to Duffy boats):
    We use 1/4" packing material for the drive shaft
    We use 5/32" for the rudder packing material

    My boat had a table that we removed, anyone have suggestions for a nice looking plate to cover this hole?
    IMG_2694.jpg
  5. Ted Graham

    Ted Graham New Member

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    It turns out that deck plates are common and come in standard sizes. This was easy to find at West Marine. I’ll try to ask harder questions from now on.
    Fishtigua and leeky like this.
  6. Fishtigua

    Fishtigua Senior Member

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    Ted, you're learning through experience like the rest of us did. You just happen to have a gang of mates to help you along the way.
  7. Ted Graham

    Ted Graham New Member

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    After re-packing the shaft packing gland I found another leak. The plate below the rudder packing gland is broken, see video. I've reached out ElectraCraft to get a new one.

    In the meantime, does anyone have experience with Flex Sealer or Stay Afloat? I'm looking for a temporary fix since the local boat mechanic is booked weeks out and the replacement seems like a big job. Our lake is small, you can't get more than 5 minutes away from our lift and the bilge pump easily keeps up so I'm not worried about sinking.

  8. Fishtigua

    Fishtigua Senior Member

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    With Mr. Boatbuilder head on, I would pull the boat out and do a proper repair.

    As a regular boat guy, Meh, I can live with that. Do it in the winter unless it gets bad. We're on a lake for heavensake.
  9. Ted Graham

    Ted Graham New Member

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    I used JP Water Weld and it fixed the leak more easily than I expected.
  10. Sailor G

    Sailor G New Member

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    Hi, everyone. I'm really happy I found this forum, there's some really useful information in here! And sorry for the long post.

    I'm in the process of buying an inexpensive Duffy 18 foot boat (Sung Harbor I think). The boat doesn't run but the body seems to be in good shape. I'm hoping to clean it up and replace the motor, batteries (lithium) and other electrical components. I don't have any experience with this but, I'm hoping to learn and am I'm no rush.

    Any advice on everything I should check before I buy the Duffy? I've already asked for registration documents and service records. Also, if I had to assume that I have to change all the electrical components on the boat (motor, controller etc) and upgrade to lithium batteries, how much should I estimate as my budget? Any recommendations for which motor to buy? And recommendations for sites or stores for all the other parts? Anything else I should think about or consider before buying the boat?
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  11. SeaEric

    SeaEric YF Historian

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    Keep in mind that typically, there's nothing more expensive (in the long run) than a cheap boat.
    chesapeake46, Capt Ralph and Sailor G like this.
  12. Rob Houston

    Rob Houston New Member

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    Well, depending on the motor, battery, charger, and controller you buy, you are probably looking at between $8-$10K. You might consider checking with an electric motor shop to see if your motor can be salvaged and rebuilt. It's also possible that the controller will still be working, so I'd check that, too. These could save you considerable money, if they can be easily returned to working order.

    In terms of lithium-ion batteries, they can vary greatly in price. I installed a one-piece 48V 160Ah NMC battery in my Duffy from this guy almost 2 years ago, and I've been happy with the result so far:

    Hi-Powerbatteries

    Good luck with the project, and please post back with your results!